06 tdi low boost P0299

[@kmweek]

Amaizing video with complete information from start to finish. That is the way it should be done. My hats off to you sir. You will have my undenying attention from now on. Cheers. From year of the vehicle, symptom of the problem. Step by step inspection of the system Andy why you are doing it and finally the cause of the problem. The fix and finally the graph test confirming everything is running great. Just simply amaizing.

[@CoolAirVw]

wow! Thanks for the complement!

[@MetaloMan007]

Hats off sir. Thank you so much for your efforts.

[@CoolAirVw]

@@MetaloMan007 your welcome

[@ableFarmer-kl7vb]

You have the best VW videos thank you

[@robmule4647]

Excellent diagnosis skills, some people think all main dealership garage mechanics are massively competent and thorough like this guy, if only.

[@CoolAirVw]

thanks

[@jamesdahmer5027]

literally the only true video that explains vacuum pressure, vnt boost control, and n75 with any significance on youtube. thank you!

[@CoolAirVw]

awe shucks! Thanks

[@mikedoherty5180]

Thank you! you just saved me several hours of research. I did short cut some of your checks. I did find the muscle line to the N75 split. A quick section of hose to replace the moulded 1. All Ops normal! Test drive improvement Proved a good fix. I'll pretty it up later, back up and running for the rest of the work week!! THANK YOU!!

[@CoolAirVw]

Well then, NICE DIAG to you!

[@CharlieMac53]

I have now subscribed to your channel after watching this video. It is very satisfying to see a mechanic who knows what they are doing. I'll bet you are never short of work. Thank you.

[@CoolAirVw]

thanks!

[@desmondou]

U have got patience n knowledge hard to find a good tech like u well done

[@CoolAirVw]

thanks

[@justincace5517]

They did this because the PCV valve that you pointed to failed, and they went internet spelunking for an answer. Someone on some club told them to drill a hole to give them a handle to pry that cover off and removed all the baffling. After the surgery they put a "dab" of rtv that seals it... for a few .. It's a "mod" that was removed from the forums back in 2018 ish. SO MANY people drilled holes in this and then RTV'ed over the hole when the PCV was stuck closed sucking oil into the intake and through the PCV system. It later gets sucked in or blown off then this condition presents itself.

[@jordandodd4141]

Great trouble shooting video my guy. Just went through a similar situation, the main feed line from the vacuum pump was clogged with carbon build up resulting in weak vacuum supply to my turbo boost solenoid. Also my valve cover vacuum line needed to be plugged to maintain vacuum which makes me think there is a second failure along with the carbon build up. Suspect the vacuum reservoir in the valve cover has some internal failure. Plugged the hose and test drove and def have boost again, will order a valve cover ~$475 and see if that is the last piece of the puzzle! Good work!

[@CoolAirVw]

get a used one or use a vacuum reservoir from a older one that is external of the VC.

[@RingZero]

I have a 04 Jetta TDI and never knew how vacuum circuit worked. You clearly explained each component for a idiot like me to understand, thank you very much Sir!!

[@CoolAirVw]

thanks

[@thecomanche1]

I've used this info to perform the test. Thanks for posting.

[@CoolAirVw]

your welcome

[@adrianpadurariu3801]

You are great!!! With your video I discovered why I had this error. All mechanics I visited Sayed the wastegate needs to be changed. But in the end it was just a hose loose! Solved with you and a obd 2 scanner ! Keep up the good work! Forgot to mention 2011 VW polo

[@CoolAirVw]

thanks for the kind words

[@adrianadrian9479]

poti sa imi scri in romana cum ai rezolvat problema?

[@CoolAirVw]

@@adrianadrian9479 Nu, nu pot. Dar dacă vizionați videoclipul puteți vedea ce parte am înlocuit.

[@edmondbytyqi4708]

Absolutely wonderful video. Well done mate.

[@lloyd-qt1mg]

WOW ... now this is the video if been trawling trough KZbin for ever! A rare find indeed - all the evidence and the solution backed up with graphs - a demo that's punching way above it's own weight!! Thank you so much for sharing your deep knowledge on this subject. I'm sure I'll find the solution to why my Peugeot 308 's thrown up a P0299 Code.

[@CoolAirVw]

I have other video's on P0299. Thanks for the compliments

[@Mac_F87]

I have a similar intermittent limp mode and lack of boost. The problem is when I scan with VCDS I have no relevant fault codes for under or overboost. Also when limp mode is present I log with VCDS I get zero boost a lower rpm and N75 drops to around 20% duty cycle. Switch off and on again and power is restored and boost builds, all be it with a bit of lag. I’m fairly sure all the cars I’ve had previously the actual follows requested fairly closely. I have ordered a mityvac to try and help track the issue down.

[@CoolAirVw]

I hear this alot, but I dont think its real. Sometimes overboost codes "disappear" when you cycle the key. Scan it right when it happens without turning off the car and I'll bet you get a code. Or maybe your scanner is crap.

[@Mac_F87]

@@CoolAirVw that’s the problem, I took my laptop with me and scanned it right away without cycling the ignition. Still no code. I also have Hex V2 bought from an authorised Ross Tech dealer here in the UK so it’s not that either.

[@CoolAirVw]

@@Mac_F87 Ok. Do you have a lack of power that clears up after cycling the key?

[@Mac_F87]

@@CoolAirVw yes exactly that buddy. The limp mode seems to happen intermittently also. I mean it’s intermittent but it happens at least once every time I drive it. The van was tuned when the second last owner before me had it. On the logs you do see it overboost slightly under full throttle. Requested is 2100mb-2300mb but that never causes the limp mode or triggers a fault code. I’ve seen many people say it happens to them when they demand heavy load from the engine. As in full throttle or going up a steep incline. Mine seems to be more partial throttle light load. The thing is 99% of these people get an associated fault code. It’s really got me puzzled anyway. I’ve been away with work for two weeks but when I get home tomorrow I’m going to check vacuum supply, check the N75, check the vacuum reservoir and also check for turbine shaft play on the turbo. I checked the VNT shaft before going away to work and it seemed to be fine, full range of motion and returned to its testing position freely. What I really don’t get is why I don’t get over boost or under boost codes.

[@CoolAirVw]

@@Mac_F87 Try again. I've had customers say "no codes" many times. Then I check and there are none. Then I reproduce the issue and I have a code. If that isn't the case with yours I don't have an answer. My opinion is certain software versions in the engine computer will "erase" boost codes for no reason, but in my experience the code is there when the limp mode happens. Logic would say if it is truly limp mode the computer is "limping" for a reason. It only makes sense that it would limp for a code. If yours is different I have no answer. But if I had one here behaving that way I would diagnose as if it had the code, but the next step for me whether it had the code or not would be to graph boost and see what is happening.

[@eklein3904]

A great & concise visual display of fault finding...thank you.

[@CoolAirVw]

Thanks.

[@51coronet]

This has been a great video. I have a turbo issue on my 06 and this will be my reference video for diagnosing it. Thanks so much!

[@CoolAirVw]

Glad it helped

[@henkotto5542]

Great video! I went through a similar process of trying to find the cause of my power loss, which turned out to be pinched vacuum hose. I now have a new issue unfortunately, which is that the power delivery is like my old 2 stroke Yamaha 350! At about 2500 rpm the power kicks in very abruptly. I've ordered a new N75 valve as I've checked that the variable vane actuator moves smoothly when applying vacuum with my vacuum pump, so it doesn't seem as though it's the mechanism jammed. Steps so far: Cleaned MAF using MAF cleaner Stripped and cleaned EGR valve (no significant carbon buildup but at least now it's clean) 2008 103kW / 140HP 2.0 TDI Tiguan

[@CoolAirVw]

If you have an 06 like this one there is a smoke and hesitation problem that can be solved.

[@chrise202]

Thank you very much for posting this. It helped me a lot understanding how the vacuum system works. I will perform a similar test on mine as yesterday suddenly the power dropped and the car was not pulling more than 2100 rpm. I could not hear the turbo either..

[@Wrensspeedshop]

I’m going to have to look at my vacuum lines. I’ve two Jettas that are identical with one being a manual and the other is a dsg. The manual feels like if you barely take the throttle it’s very responsive, where as the dsg Jetta definitely has lag to it. It’s gets great fuel economy, but every so often goes into limp mode which is a pain especially if you’re on the highway. Thanks again.

[@CoolAirVw]

thanks for watching.

[@Vcoldduck]

I wish I could find a shop like yours here in Fla. I've been at the jaws of a dealership for the things I don't know about. The turbo tear down was great and you can bet they would want to sell a turbo. I could go on and on. I'm glad to have found you and if you know anybody in or about Parrish, Fla. that works on VW's even Tampa let me know. The scanner info is great I'm looking into Hack your car so I don't have to but a scanner but have the program on my computer. I'm doing my best to learn how to keep my 06 Jetta TDI.

[@santhansanthan4839]

Super super super it's very useful for me. Thank you so much

[@CoolAirVw]

your welcome

[@DanSohan]

Thanks, very nice video explaining vacuum fault finding at its best! Basic tools, effect fix!

[@CoolAirVw]

I appreciate the compliment. Your welcome.

[@sat_sonic]

One of the best diagnosis videos I’ve seen in a long time. Thanks again for the excellent video and explanation.

[@CoolAirVw]

Thanks for watching.

[@caseymills9]

recently had very simillar problem. traced the vacuum lines and saw one had fallen off its clip and worn a hole by contacted the axle. $7 fix. Excellent video. I'd like to see the opposites of some of your findings in this video. Like what if the vacuum had been bad at the pump, or solenoid, or if the plunger hadn't gone all the way down. Great vid!

[@CoolAirVw]

thanks for watching. More videos coming. Maybe one will come in with a problem like what your describing.

[@thomast4479]

Many thanks for the video sir. I used your video as a reference and checked the source vacuum on my 2014 Jetta TDI and its only generating 12hg of vacuum! Looks like I might be having a bad vacuum pump. My brake pedal go hard when I press brakes repeatedly in a short period of time. Car also feels sluggish .

[@jamesdahmer5027]

at 14:43, you cycle the on/off of the n75 valve - are you doing that manually or by operating VCDS? does the computer normally elevate to 25mmhg of vacuum then 0? Mine sits at 25psi and does not fluctuate.

[@CoolAirVw]

scan tool puts engine computer in a test mode that cylcles it. If yours isn't fluctuating then either the test isn't happening or the solenoid is stuck open or the computer is incapable of closing the valve.

[@szamanisticrealistic2659]

Had this error code alongside a few other indicating the same issue. It turned out to be a single small hose that chipped a bit at the end slipping off. I cut it off a bit at the end and it's all back to normal now. It was a small hose located just over the turbo.

[@CoolAirVw]

excellent!

[@denyboy97]

OOOOOhhhh... 🙃Well, that explains everything. I accidentally damaged my Valve cover and attempted to reseal it with epoxy and high temp silicone, quite clearly that has failed, little had I known the damaged section was a reservoir for one of the vacuum lines 🙈. I did trace the pneumatic lines and ssimilarto what you showed in this video, the line is fed to a solenoid which feeds two other vacuum lines but iIwas naive and only presumed it wouldn't affect my boost levels Dah🙄. I had been getting the following codes P0299 and P2564 but found no fault on my actuator, therefore, the damaged cover must be the culprit, luckily I have already ordered a new cover and stumbled across this awesome video in the process of fault finding various causes and fixes for this issue. Here is to more Boost 🍻 Many Thanks CoolAirVW Rm 😁👍🏾

[@CoolAirVw]

Best comment ever! Thanks! Its nice to be appreciated.

[@pauliekruger7639]

Junk Yard, recycle.

[@GWAYGWAY1]

Being a cheapskate I would have put a self tapping screw in that hole, much cheaper than making VW richer.

[@CoolAirVw]

Certainly was an option and was considered. Customer wasn't cheap though and after considering that the cover had been broken off and glued back in place we thought it might be nice to have it right, for longevity.

[@ninjagame69]

Photography is not enough

[@51coronet]

Or JB weld it shut haha. I would do the exact same.

[@richardmathers7238]

Best video I’ve seen that explains test for vacuum 👌

[@CoolAirVw]

thanks

[@rickharris5485]

Great video. Thanks for making it. My guess is some crooked mechanic, in the car's past, drilled that hole.

[@CoolAirVw]

maybe but remember the cap was broken off and glued back on for some reason.

[@josepeixoto3384]

nice catch,and also you got it easy; suppose the engine ECU had gone astray and was commanding the N75 wrong, now that would have been a job; have a 2004 Laguna 1.9 DCI here with the opposite problem (takes off slow,then goes to over 2.5 bar of boost, scary fast,and i'm running out of options!! everything is ok, no check eng.light,no error codes... but the ECUs on these sit under the battery,very low, and they are prone to heavy corrosion on the terminals...

[@jaykent6645]

Brilliant and thank you, your info was so comprehensive. Wonderful Kind regards Jay

[@CoolAirVw]

Glad it was helpful!

[@philiphiggins4822]

Excellent video ive got s vacuum hand pump on the way, bit this video has shown me what to do, my engine is a bkd, and has a vac box instead of the n75 and egr one

[@CoolAirVw]

thanks for watching and I appreciate toe t positive comments.

[@AjmalKhan-rq5xu]

Very sequential and systematic test. I have the same issues with the tdi passat. I have ordered the handheld vaccuum pump and will test and update. Will be hard to find the actual line but will update what happens. Thanks again

[@AjmalKhan-rq5xu]

Mechanic said the whole turbo needs to change which is £1600. But will test it in the sequence you did to find the exact problem. Hopefully it is something minor

[@CoolAirVw]

@@AjmalKhan-rq5xu what year passat do you have?

[@atikovi1]

Very useful video. I have a similar problem on the exact same car. I had the turbo rebuilt by a reputable turbo rebuilder, installed it, and the car runs like crap. No power until 2200 rpm, black smoke, rapping noise, acidic smell from under the hood like the converter is overheating. It ran better BEFORE the rebuild. If I remove the hose from the VNT actuator it's a whole different animal. Tons of smooth power, no significant smoke or noise. Ran some tests. Put vacuum to the actuator and the rod moves smoothly and holds vacuum. Checked the solenoid and it puts out good vacuum to the valve. Do have the code P0299 low boost. What to check next?

[@CoolAirVw]

black smoke and low boost probably means a boost leak. Look for splits in hoses or disconnected hoses. I have a video on a boost leak, but its a different car. Point of me sharing this video link is, smoke plus low boost is boost leak. kzbin.info/www/bejne/fX7UoXyclptmoKM

[@lennycook206]

New turbo Chra fitted on golf plus 1.9tdi and now black smoke. Will a bad actuator do this?

[@CoolAirVw]

boost leak will.

[@lennycook206]

@@CoolAirVw got a vaccum gauge on order.... Thanks for reply

[@lennycook206]

So my car is fine now. New turbo CHRA, new actuator as diaphragm was damaged. New egr valve as diaphragm was damaged and a new vacuum solenoid as it was also damaged. Took a while to get it all sorted as I'm not a mechanic. I'm amazed how 3 components all failed but I assume me driving 5k miles with a howling turbo was probably stupid and caused all the carnage. Makes a mockery of all the YT comments claiming their car ran for 60k miles with no problem, whilst their turbos howled like a siren and how cool it sounded Think they were telling porky pies. And yes a handvac tester is vital. Thanks. Ps I can now remove a turbo in a mk5 golf plus 1.9tdi in 41 minutes! I've done it 3 times now and I'm pretty good at it lol ☺️

[@CoolAirVw]

@@lennycook206 air tools?

[@lennycook206]

@@CoolAirVw no, socket set, swan neck spanners and Allen keys.

[@wackey3455]

HI I KNOW THIS VIDEO WAS MADE FIVE YEARS AGO BUT IS THERE ANY CHANCE YOU WOULD TELL ME WHAT YOUR TAUGHT ON MY VW GOLF MK6 I HAVE NO BOOST FROM THE TUBOR AND WHEN I DRIVE IT THE CAR HEATS UP SMOKE COMES OUT OF THE TUBOR WOULD YOU BE ABLE TO GIVE ME ANY DIRECTION PLEASE I CANT AFFORD TO BRING IT TO A GARAGE AT THE MOMENT

[@CoolAirVw]

No boost and smoke? Tdi? Maybe boost leak. I have a video showing a boost leak on a tdi.

[@wackey3455]

@@CoolAirVw Thanks I have a look at that now

[@JohnDoe-sd4ou]

Richard where is ur shop at?

[@CoolAirVw]

kansas city area. (thats missouri)

[@JohnDoe-sd4ou]

@@CoolAirVw Thank you....

[@math9254]

Best vid so far to approach this issue...great job, superb!!

[@CoolAirVw]

thanks for the complement

[@michaelschneider-]

+1. .. Excellent vacuum tutorial specific to the 1.9l BRM TDI. .. Our 2006 Jetta 1.9 BRM has a similar if not the same driving condition as your 1.9l TDI Jetta; soft power and occasional limp mode. .. I have diagnostic's to get with. .. Have VCDS, will travel. .. Thanks!

[@CoolAirVw]

got another BRM P0299 code video coming up.

[@stevetonnesen3666]

So I had a similar problem, but no one had drilled a hole. What happened is that the glue joint VW had between the part you showed and the plastic cylinder head cover casting had developed a leak. I simply applied a silicone seal around the entire joint, which eliminated the vacuum leak and solved my problem. You could have saved quite a bit of money by simply similarly plugging the hole with silicone rubber.

[@CoolAirVw]

Very good to know. Of course plugging the hole was an option, but with the part being broken off and the fact that it was for a customer I had to guarantee it was a good fix. Plugging the hole has been mentioned before in the comments.

[@guayaco-dm3vu]

Excellent Diagnose Boss... Will keep this in my notes for my very own vw repair manual...Lol

[@CoolAirVw]

Just dont drill holes in the VC and you'll be set.

[@wackey3455]

Came across this video after searching the web for to weeks. Invokes like you know what your doing very concise. I'm just wondering if you could help me please. My mk6 golf dsg i changed out the master cylinder and started bleeding the brakes everything was grand till I got to the back wheel with the bleed screw open my helper pumps breake pedal and it went stiff so I taught job done so I got into the car started it up and the breake was like a brick. With hardly any breake at all. Did I put the master cylinder in wrong as it was very hard to pull out and when I put the new one in it just slid in and out no resistance. Any help really appreciate it

[@CoolAirVw]

is there vacuum to the brake booster? Is the plastic hose that goes to the booster cracked?

[@wackey3455]

🤩

[@wackey3455]

Yeah after looking at your video it gave me great clues so I was listening out for hissing it turn out that when I was taken the master cylinder out I slightly knocked the breake booster harness out couldn't be leave such a simple thing would give me very little breake and my car went into limp mode. Thanks for putting me in the right direction. Your videos are the best I came across on you tube great work

[@CoolAirVw]

@@wackey3455 I'm glad I was able to help.

[@charlescoomer125]

So I am having the same issues as what the vehicle in the video is having. I found a couple vacuum lines that has holes in them. I replaced every vacuum line I could. I'm getting 25 inches of mercury from source vacuum but only 15 at n75 valve. No holes in the valve cover no other vacuum lines to be replaced.

[@03056932]

When repeating your tests on a BLS, my vacuum at the tandem pump was good - 25. But I realised actuation of the egr solenoid (n345?) was robbing vacuum and what was getting to the n75 was sometimes 25 and other times just 5. If I unplugged the egr solenoid the n75 would always receive 25. With the egr solenoid connected, blipping the throttle would also instantly trigger vacuum entering the n75 to drop to 5 indefinetely. Would you be so kind as to advise whether you think this is a faulty egr solenoid? Surely it shouldn't randomly leave the n75 with virtually no vacuum to work with? Strangely my codes were an occasional P0299 and a couple of glow plug open circuits. With the way my vacuum to the n75 is behaving I would have expected very erratic boost. But when it isn't sent into limp mode the power and response is great. Confusing. Any insights from your knowledge is very much appreciated.

[@CoolAirVw]

No it should not. You didn't state year make model, but I'll assume its something similar to the 06 in the video. The valve cover has a vacuum chamber built in to supply with vacuum if there is "low vacuum circumstance" also there is a one way check valve to seperate "important" vacuum functions from not so critical functions. Check those things.

[@03056932]

@@CoolAirVw golf 2008 1.9tdi BLS. I just tested the vacuum line going from the egr exhaust cooler solenoid to the exhaust cooler and it holds no vacuum. Which is typical because its hard to access and I'm reading to replace the diaphragm of the valve I would have to replace the whole cooler and not just the valve controller stem which I see in parts stores. Have you dealt with this part much? Seems like the bls is less common than the (seemingly) simpler and better designed ALH etc. Thanks again for any help

[@naamiazar3371]

Bonjour monsieur Bravo Pour votre bon diagnostic Vous permettez, juste une question Sur le graffe on vois la couleur qui est la pression demander par le calculateur Par Contre si la pression réel qui est de couleur jaune n'apparaît pas sur le graffe A ce moment là à votre avis c'est quoi le problème ?

[@CoolAirVw]

Si votre ligne jaune ne s'affiche pas sur le graphique, l'échelle est peut-être mal définie. Quel nombre est affiché dans le groupe 11 champ 3 ?

[@krcright9746]

2014 VW 2.0 tdi. It had an underboost issue p0299 edof last year, It had a new turbo fitted this January. Shaft / bearings had worn, Veins has seized up and It has been fine up until 2 weeks ago. once again got the p0299 underboost. I’ve Checked all vac pipes Vac pump Checked the n75 Checked the actuator travel and diaphragm Checked all boost pipes, clamps ect Fitted a new EGR and the checked the exhaust had carbon built up.... Any ideas? Thanks

[@paulwaclawek2149]

That’s a great video…..you know yr stuff…. Shame most garages don’t…. Wished you was by me😳

[@CoolAirVw]

thanks

[@umuttokatli65]

Well done very good vid. One qstn though, in fixed condition of error, what is the reaction time to turbo after you floor the throttle in terms of seconds?

[@CoolAirVw]

thanks for watching.

[@umuttokatli65]

@@CoolAirVw you are welcome. And what is the response time of turbo to throttle??

[@dez945able]

is this a cause even you can move the turbo actuator high enough - by hand Do you think it still could be fullc arbon ? cause i can move it the turbo actuator all the way, but i can feel it its not so smoothly / i did the clean the turbo with oven cleaner and its much better move now; might i wrong; do you think i should buy a new turbo from Volkswagen thanks so much, i think you help lot of people

[@CoolAirVw]

I do not know.

[@rowdyrickshallr9305]

Enjoy your videos a lot. Thank you. I would think a bit costly to purchase a new valve cover when the hole could be easily sealed shut with a simple patch etc. Minor detail tho.. Love the diagnostics!

[@CoolAirVw]

Lots of people have commented that allready but I would guess few of them watched to the end where the cap of the valve cover was shown that it was broken off and glued back on.

[@rowdyrickshallr9305]

@@CoolAirVw Thanks for the reply. i watched thru. Makes sense now. I had figured it was just customer's wish. Keep the vids coming. I learned a good deal here to use on my Tdi. Your videos are easy to watch. Talking things thru as you work is awesome. Thank you. 👍

[@Ni1kko]

Hi mate, i have simler issue and no one can see to find my issue. i have changed and swapped everything. i have a bigger turbo fitted and mapped. was runninng fine in my a4 sallon but now i changed to avant same engine code and put my turbo and ecu on to the avant. but if i rev car and hit breaks i lose all vac. if i drive and press my brakes the brake pedal goes rock solid. Could this setup require something like boost bottle to hold more vac or do you think tandem pump is going? N75 is replaced and simplified, no egr or flaps. vac line come from main vac too the N75 then from n75 to turbo actuator. Car is AUDI A4 B7 Avant Quattro 2.0TDI BLB PD140 (Ecu is from 2005) body is 2007. Some mechanical mods (Witch i had on my saloon and had no issues was mapped by FADR) 120% injectors nozzles GTD2263VZK running (3.1bar) BKD Inlet (flaps delete) EGR Delete ASV Delete MAF Delete try to give you as much info as i could hope you have some ideas i can try.

[@CoolAirVw]

Dont know.

[@Ni1kko]

@@CoolAirVw bit blunt but thanks anyway worth a try.

[@ncut5547]

That's a real good research into that vacuum side of things ...dont know if u can remember but I asked about hydrolocking on a 2002 jetta well it turned to be good after I changed out the charge air cooler with a new one car drives good ...but I have a similar problem as u just described loss of power but it will come and go as you drive the car would it be possible for the vacuum side to cause that type of symptom...thk you for your videos they are very helpful keep up the good work.

[@CoolAirVw]

Yes it is possible.

[@elena6688]

Hello! I have a Golf 6 2.0 TDI, replaced turbo, new N47 turbo solenoid, new vacuum acutator, new intercooler, hoses are fine, everything fine, did a DPF OFF and stage 1 on it, but GETTING this P0299 UNDERBOOST and I really don t know what to do, every test of vacuum fine, replaced engine cover as well

[@elena6688]

Should the stage 1 not being configured properly or what could be the problem?

[@CoolAirVw]

@@elena6688 I doubt it. Sorry too complex of an issue for me to answer intelligently. p0299 is boost leaks or vacuum control or actuator adjustment. If you've done all that, then your missing something.

[@CoolAirVw]

@@elena6688 you should probably watch the following video. Maybe it will have some info in it that you can find the solution to your problem. kzbin.info/www/bejne/Z4umqWmYi7BpncU

[@elena6688]

@@CoolAirVw Well, vacuum leaks no doubt about it, checked and nothing, actuator position is great, i don t really know what could be that p0299

[@elena6688]

@@CoolAirVw I will check it thanks

[@Markb8608]

did you make a video on camshaft replacement too. I didn't see it.

[@CoolAirVw]

No I didn't. Maybe someday. But really my channel is more focused on Diagnosis and not "How-to". Its difficult to put in all the details necessary on a major job like a cam replacement and make a quality video.

[@jaycee7841]

Question ... If the hole was there all the time ...why was the fault intermittent ? Surely a leak that was there all the time would always trigger a code and limp mode .. I'd love an explanation.

[@CoolAirVw]

It takes a certain amount of driving with the fault present to make the code reoccur. I wasn't driving it hard enough, long enough.

[@jaycee7841]

@@CoolAirVw - Thanks for the reply , since i wrote , following your guide I used a vacuum gauge ( different make same idea ) .. and connected it to the line feeding the actuator , then I ran the test procedure for the N75 as you did ... Its building /holding and releasing vacuum as normal . After that I looked around with a flash lamp and noticed a large rubber bottom pipe had been rubbing against a bracket and it appears to have worn a good deep groove in it .. for the moment , i have wrapped / sealed it with gorilla tape to see if that makes any difference .. the pipe appears to be routed from what i assume is the intercooler to turbo ... any chance its the culprit ?

[@CoolAirVw]

@@jaycee7841 yes, a boost leak will cause low boost trouble code. I have another video on boost leaks.

[@jaycee7841]

@@CoolAirVw thank you I'll look

[@justinsanders195]

Thanks for the video. Very informative.

[@CoolAirVw]

your welcome

[@Mikefngarage]

good job finding that took some tracing.

[@CoolAirVw]

thanks for watching.

[@barry6873]

Excellent video I’m doing turbo on my Ford Focus at moment but I wish ide seen these videos before may not be my turbo

[@CoolAirVw]

Obviously some of the SAME DIAGNOSIS STRATEY MIGHT APPLY TO OTHER TURBO CARS .

[@roncampbell4121]

Great video, my 2006 VW Jetta TDI has similar problem, goes into limp mode. I am not willing to pay VW what they want to fix my car's problem. I can at least tackle this problem with some education on what to look for.

[@CoolAirVw]

thanks.

[@LeeRoyJuniour]

I’ve got the newer 105 engine and there’s no tutorials on it for p0299 all boost pipes on turbo trying to boost but just vibrating

[@bartswedin1119]

You said you replaced the cam 6 months earlier, was the hole in the cover at that time, why did someone drill it

[@CoolAirVw]

Yes it was. Watch the end of the video

[@rsage_]

Brilliant video. Lots of really good info on this issue. I've got the exact car with the same issue. Planning on digging into it tomorrow.

[@CoolAirVw]

Thank you. Very common for the turbo actuator diaphram to be ruptured. Look for vacuum leaks also.

[@rsage_]

Question: I've got a 2006 Jetta TDI (BRM) with an automatic transmission. I'm getting a low boost code (P0299) and can't find any vacuum leaks. When I connect the vacuum line to the N75 (pressure converter), it seems as though it sends full vacuum to the turbo actuator (the actuator holds vacuum just fine and is set to open at around 3-5 PSI vacuum and fully opened at 18-20 PSI), thus forcing it to open completely and run horribly. Do you know if the actuator is supposed to send full vacuum to the actuator at idle?Hope that all makes sense.

[@CoolAirVw]

I think your question is answered at 13:43 in the video.

[@rsage_]

Thanks, so I guess I'm getting the exact same vacuum from there, but for some reason when I connect it (as seen at 13:45) to the actuator the car starts running horribly. I can see the pin in the actuator drop all the way down. It has a new turbo on it and I know the veins are moving just fine.

[@CoolAirVw]

Thats strange. Can you define what you mean by "runs horribly"? Are you still driving it? What brand or supplier is the new turbo from? Does it trigger trouble codes? Have you inspected for camshaft wear? Camshaft wear problem would be very evident if the intake tube was removed from the intake (at ASV/ EGR ) valve and you ran the engine. It would sound like popping from intake usually.

[@Banker.xXxXxX]

Mine car goes into safe mode on a highway after 40min. City drive does not habe anny issues you can drive as fast as you will turbo is working perfectly. On a highway slightl hill it goes into limp mode. On off und he is doing great again for sometime you cant predoct when will he get in limp mode. Po299 underboost code. All leaks habe been checked intercooler changed. Could it be n75? Turbo should not be a problem, can you help please??

[@sertancan6185]

Hi great video 👍i have changed my camshafts on my audi a6 2.0tdi 2006 after an timingbelt failure and now i have p0299 fault code underboost. That is the only fault code and i have tested the n75 valve everthing works no leaks so i think it is caused by the camshafts. How can i be sure?

[@CoolAirVw]

probably not aused by the camshafts.

[@yengel7442]

hi is there a fuse for solenoid valve n75 golf 6 tdi

[@CoolAirVw]

I dont have them all memorized. I know for a fact there is a fuse for the mk4 cars and that fuse powers several items (will trigger several codes) but I'm just not sure on your car.

[@linwizz2126]

Wonder if you could have just bought a ball like the mk4's have and find a place to bolt it in.

[@CoolAirVw]

There have been bunches of comments regarding plugging the hole or other repairs that might have saved the customer money. I'm all for that. Just make sure you watch the end of the video where we find the cover was broken off and siliconed back in place. This customer loved their Tdi and wanted it RIGHT! Unfortunatly, later they crashed the car, I bought it, then fixed it then sold it, and am still working on it for the new owner. I also still work on the original customers new car which is a later tdi. Sometimes for the sake of longevity, fixing it the right way might have benefits. Of course if your a DIY'er just do any fix you feel will work, because if it dont work or last then you can only blame yourself. If the mechanic does some improvised fix and it doesn't work or last, of course then he is blamed.

[@AndersMcTee]

I have this code on mine. Turbo lag and black smoke. I changed the MAP sensor which has improved the smoking a lot but it still holds back a bit and then boosts. Il check all my vac pipes tomorrow.

[@CoolAirVw]

turbo lag and smoke... holds back a bit then boosts. I would assume you have the "smoke and hesitation problem" usually fixed by adjusting the turbo stop. Through the course of time and wear, the vanes end up closing all the way and stick in the closed position which basically blocks exhaust airflow through the turbo vanes. Dealer will sell you a turbo, which would fix it but you can usually fix it by adjusting the turbo stop so that the actuator never goes to that closed vane" position.

[@CoolAirVw]

Here is the thread where years ago, some sharp guys solved the issue. forums.tdiclub.com/showthread.php?t=280804

[@CoolAirVw]

pay close attention to thread 47, 62 and 63. In thread 63 there are two videos that show the problem clearly.

[@CoolAirVw]

FYI this can be fixed in the car without removing the turbo, we have done it dozens of times.

[@CoolAirVw]

There is also what "they" call zip tie MOD, where they zip tie the actuator where it wont go to the closed vane position.

[@safindll6558]

Thank you very much for your video excellent

[@CoolAirVw]

Your welcome!

[@dez945able]

hi just one question, can I clean turbo on Passat b5 with special spay to spray it inside the EGR valve when the car is on with full power around 4000 rev engin

[@CoolAirVw]

uh, you can do whatever you want. Lots of people try improvised cleaning methods. I dont know that I would rev the engine to 4000 that might be a it excessive. Personally I wouldn't spray anything in the intake (or egr)

[@dez945able]

thank you so much, do you have a video that how to clean turbo, thanks Passat b5.5 1.9 TDI. 130 hp I think you only smart person around me

[@MrJeepin88]

Any specs on the alh for output tests on the vacuum I’m getting ready to replace all my vacuum lines because they are worn pretty good and plan on doing these tests on mine for good measure

[@CoolAirVw]

See my other video kzbin.info/www/bejne/ZmOue6uEo76ckM0

[@bradykice8759]

Where did you get this vacuum pump, I want to try to diagnose the problem myself first on the car

[@CoolAirVw]

you can get this style of hand vacuum pump everywhere. Oreilly auto parts carries them. Harbor freight has a crappy one. Amazon, ebay ect.

[@jonwalsh589]

I have a vow caddy 1.9tdi that goes into limp mode bringing on p0299 low boost If I clear the code the van flys and can be like this for days and sometimes it will last for minutes before it goes back to limp mode I have had it smoked tested for leaks and it was ok When the code is clear the van boosts very well and if you clear the code when going along it will fly again Any help on this

[@CoolAirVw]

try the tests in the video

[@mathewhoffer4541]

Nice video on logic based diagnostics and how a thorough testing will keep you from buying loads of parts willy nilly on guessing at the customers expense .. valve cover was probably pricey ? why not RTV and plug the holes with a lag bolt and RTV and call it a day ? not very professional yeah but did the customer really need a shiny new valve cover for an easy fix ? if it was a lambo or a bugatti yeah sure but a VW ? wire ties and duct tape is what these things are held together with.

[@CoolAirVw]

You didn't watch the end of the video where we noticed the whole cover had been off and someone "glued it back on". Lots of people had suggested plugging the hole and thats fine, but these customers wanted the car to be nice, and right. This car was eventually wrecked, sold to me, rebuilt, then sold and I still talk to the owners now and then. Original owners bought another tdi and I service it for them as well.

[@toddgriffin4596]

So what happens when you do all the tests and there's no vacuum at all. Have you seen the vacuum pump itself Go out or be bad? Or do you have a video on how to diagnose the pump itself??

[@CoolAirVw]

Hook your vacuum gauge as close as possible to the vacuum pump. Eliminate any change of huge leaks at the booster or boost er line by visual inspection and disconnecting the line from the booster and plugging it. I have seen a few vacuum pumps break where they engage the end of the camshaft but that was always immediately after "work done" due to rough handling.

[@toddgriffin4596]

@@CoolAirVw yep I went straight to the pump. Pump was working well so I unhooked the spaghetti of lines, finally I stuck a wire through the little check valve that's in there and now I have turbo so I have a bad check valve that's in the one vacuum hose. 🤦🏻‍♂️

[@CoolAirVw]

@@toddgriffin4596 Excellent diag.

[@ajith2759]

Very informative video. The turboboost solenoid valve of my polo tdi is producing a Tik-tik noise . Is the valve damaged?

[@CoolAirVw]

I wouldn't assume that the noise makes it damaged. but if it cant control vacuum then it is damaged.

[@blackskiess2858]

does this work with the check engine light? i don’t understand if my actuator is bad or if the check engine light cut power to it. i’m not great with cars so sorry if i don’t make sense

[@CoolAirVw]

The trouble code that you saw me get out of the computer using the laptop with the vagcom system will trigger a check engine light. Be sure to watch my other videos on boost problems.

[@richardroope1424]

Awesome video for both VW PD TDi and fault finding in general! I’m having similar issues with a BMN Engine. Any idea what vacuum the storage tank in the rocker cover should hold?

[@CoolAirVw]

It holds vacuum. Full amount. As much as you can pump it up with a hand pump it should seal.

[@richardroope1424]

CoolAirVw Rm thanks buddy! The system is doing about 28in mercury from the PD pump. The storage tank though is taking 20+ pumps to get up to this, and only hits about 20?. When this turbo under boost fault comes on, I heard a “pop” sound like something had unstuck (10th time in 2 days I’ve generated it on test so I know it’s not loose pipes etc)

[@CoolAirVw]

@@richardroope1424 If it doesn't bleed off after you pump it up to 20 then its probably fine.

[@rodneywise6773]

I was wondering I have a 2008 Volkswagen Passat 2.0 t my computer went into limp mode and said turbo underboost so I figured it might be my diverter valve or the Westgate but my arm come unscrewed or something from the turbo so I screwed it back on and now I'm still getting a cylinder 3 misfire I do not know what the factory settings were on it now I can drive it a few miles and then the light will start flashing and it's like it's missing and fixing to go dead I guess going back into limp mode and I get it back to the house and it is pulling up a cylinder 3 misfire I do not know if that has something to do with the turbo it seems like it runs a lot faster than what it used to any help would be greatly appreciated on how to adjust it or what the factory settings is

[@CoolAirVw]

Misfire is probably not related to turbo. Try replacing spark plugs and swapping coil packs to see if misfire moves. Of course there are lots of things that can cause misfires.

[@rodneywise6773]

@@CoolAirVw ok thanks

[@nedimmrsic4650]

i wish i have a mechanic like you in my reach..

[@CoolAirVw]

thanks for the compliment.

[@dane4890]

Me too

[@nedimmrsic4650]

@@CoolAirVw i have similar problem with my audi a4b6 1.9tdi.. when im in 2nd gear i floor it, and until it gets to 2100rpm it feels like im driving 1.0 engine, the moment i reach that 2100rpm turbo starts, and it rips tires. my ecu is ABT mapped to arround 170hp, im not sure, but i feel like it should be more agile in low rpms and have better acceleration.. any ideas of what sould i check? our mechanics here are nowhere near your knowladge lvl, pls give me some pointers.. and sry for broken engl.. :S

[@aadd3538]

$6 Sikoflex to the rescue.

[@CoolAirVw]

Yeah, there have been 1milliion comments about plugging the hole. Did you watch the end where someone had pryed the top off of the reservoir and siliconed it back on? Customer loved this car and wanted it right. But if we needed to fix it on the cheap we could have plugged the hole.

[@jakobbedholm3352]

Great video! Having code “P17705 - Pressure Drop between Turbo and Throttle Valve” on a 1.8t, stored associated with a boost problem, might want to give this diagnose a try.

[@CoolAirVw]

Not too much the same on 1.8T as this one. Look for boost leaks and check the wastegate adjustment. Lack of power or clogged cat makes boost trouble codes also. check diverter valve.

[@jakobbedholm3352]

@@CoolAirVw I know, but your way of using the gauge was well done. The N75 valve basically has the same layout, and I’m worried it could be the problem. The diverted valve is a good point too! Thanks for the reply.

[@CoolAirVw]

@@jakobbedholm3352 You cant run output tests with engine running on 1.8T so vacuum checks have to be different.

[@jakobbedholm3352]

@@CoolAirVw oh I see.. well I did some output test, and all responded. Did a smoke test and no leaks. Did a short driving log, and saw a small hiccup where the MAF sensor dropped, so i am not sure what to make of that, but a longer drive will definitely give a better reading. I did purchase a new diverted valve just for good measure.

[@CoolAirVw]

@@jakobbedholm3352 did the maf sensor drop out cause the hiccup or did the hiccup cause the maf sensor drop out?

[@generluna5456]

Hello friend, i have a gli 2006 turbo, it has a problem very very similar as this one, bur my motor is gasolined, and i was wonder, the n75 would function the same way as this TDI? The wastegate of my car opens with pressure, not vacuum like you show us on video, i apreciatte any coment or help. Thanks!!

[@Johnjacobjingleheimer9]

Is 25+ pounds the correct specification for vacuum pressure? I am having a low power problem and I am getting 18 pounds of vacuum at an idol directly off the pump. Obviously I’m leaning towards a bad vacuum pump

[@blackskiess2858]

i have been looking at my hoses and testing the vacuum, everything is super similar, i only have around 5 in. Hg at the solenoid, but my vacuum is 28in. Hg. I just have no idea where the leak is

[@dez945able]

hi, on my pasat b5,5 TDI 130 hp . my turbo actuator is working all the way with vacuum pump the same as yours But or I think the n 75 valve cannot move the A turbo actuator enough just 1 centimeter. . Do you think if i change n75 would be ok? do you think the turbo actuator should all the way up? when the car start also i didn't find any holes in vacuum pipes any idea what should I or could do thanks

[@CoolAirVw]

please explain how you came to that conclusion? Is the actuator moving all the way to the sop? If you use a hand vacuum pump will the actuator move all the way to the stop?

[@Riverap27]

hello friend, where in the US do you work, I have a problem with my vw cc car, I changed the turbo and the wastegate valve is not opening, I tried the solenoid and it has very little air pressure, it is very significant, what do you think it could be?

[@mackmeyers1603]

Hello I’m having the same intermittent limp mode issues. My turbo actuator moves in an out when I unhook the vacuum line. When cruising on the highway when not in limp mode I get s slight surge in power for a brief second. I checked for a hole no hole. Checked source vacuum is good before and after n75 valve. Is it likely my actuator or the turbo is going bad ?

[@CoolAirVw]

Thanks for watching. To know you'll have to know if your over boosting. What trouble code? Graph boost with vagcom to know. Check that the actuator holds vacuum. Run output test on solenoid to see if it works. Make the checks in the video or you might need to find someone who can.

[@dez945able]

the actuator moves all the way to the sop and when i use the hand vacuum pump the actuator move all the way to the stop

[@CoolAirVw]

well I guess its not stuck.

[@___Blessing]

Also inspect the intercooler for signs of damage.

[@davidmbell]

Any ideas why someone would have drilled a hole in the valve cover / vacuum reservoir? What would they be trying to achieve (other than causing this issue)

[@davidmbell]

And also, if you fitted a camshaft to it recently, was the hole there then, and if so, were the owners getting this issue back then too?

[@CoolAirVw]

I have no idea why someone broke the top off and drilled the hole. The customer was having intermittent limp mode before and after the cam.

[@stevenr21]

Maybe they mounted a vacuum gauge?

[@iankelly2110]

well done you did all the right diagnosing to find the fault. The hole was anyone guess some idiot more than likely.

[@CoolAirVw]

thanks

[@MrShuthwaite0578]

Super video, i have the powertrain fault every now and again, i have 2.0tdi golf mk6 2009, with 110 bhp, any help would be greatly appreciated

[@CoolAirVw]

"the powertrain fault?" You mean a overboost code like the one in the video?

[@rabmccudden683]

Is this the same Engine from a 1.9tdi A4 b7 2005? My car is constantly going into limp mode 😩

[@CoolAirVw]

i dont think that Audi was sold here (usa) with a tdi so its probably different. Some of the diagnostic process would be the same though.

[@rabmccudden683]

Thanks. Great video by the way.

[@lonewolf031]

I have a 05 golf with a similar problem.

[@lonewolf031]

@@CoolAirVw it's a tdi too, the code says low turbo boost charge.

[@CoolAirVw]

@@lonewolf031 check for boost leaks then do the tests in this video.

[@richardmathers7238]

Would a evap smoke machine have worked to find this fault as well ?

[@bluthebeast3132]

Brilliant video guys 👍🏻

[@CoolAirVw]

Thank you.

[@donwillcox6470]

Great, succinct, informative - thank you.

[@CoolAirVw]

Thanks. More boost related video's coming.

[@maxthecaddy8451]

smoke test might be good for this? Excellent video👍

[@CoolAirVw]

sure. thanks for complement.

[@dez945able]

hi, any idea how to fix this. I cleaned EGR change n75 and Intake Manifold Flap {N239} still getting limp mode Passat b5 1.9tdi 3 Faults Found: 19586 - EGR System P3130 -35-10- Regulation Range Exceeded-Intermittent 17964- Charge Pressure Control P1556 -35-10- Negative Deviation-Intermittent 19561-Valve for Intake Manifold Flap {N239} P3105 -35-10- Open or Short to Ground-Intermittent

[@CoolAirVw]

Sorry, I cant diagnose it based on what you said. I would do certain tests for each code, except 19561, almost for sure that requires Intake manifold flap assembly.

[@dez945able]

any idea really nobody can help me with this, do you think could be turbo? you know I am in Europe , but thanks you did answer it kind

[@CoolAirVw]

@@dez945able yes it could be the turbo. Do the tests in this video and others. It could also be vacuum leak, boost leak, bad actuator and other stuff.

[@dez945able]

thanks@@CoolAirVw

[@dez945able]

@@CoolAirVw just one more question, can I clean turbo with a special spray to spray it into EGR valve when car runs 4000 rev