P0401 EGR Insufficient flow test

[@JustPlainCommonSense]

Folks, That is a Real mechanic. Great job troubleshooting the problem and not being a professional parts changer.

[@JesusSaves86AB]

Although when you consider shop labor costs, most owners are better off replacing all the parts they are able to before paying for a few hours of diagnostic labor. For example, I had an 04 Altima I replaced a crank sensor for $20 myself, my boss's wife has the identical car and the shop charged them over $600. A ball joint failed on my wife's crown vic, towed it to a shop since it was a holiday weekend and I was busy, they charged over $700 for a literal $5 one on rock auto.

[@Duke_of_Prunes]

@@JesusSaves86AB Exactly. I can buy a ton of parts for $500. Even if I replace 5 wrong parts with the shotgun approach, my vehicle is 24 year old and 168K miles. The 5 "wrong" parts were on their way to failure, anyway -- and tow trucks cost big money these days.

[@dmorley100]

I think this's the best explanation I've ever heard about how to test a Ford DPFE EGR system.

[@rlgoers]

Bingo!!! I've been chasing the cause of the P0401 code on my '03 Focus for almost a year... even threw a new DPFE sensor at it. After watching your video, I pulled the vacuum hose and it looked EXACTLY like the one on your example car in the video... rubbed right through. I repaired the hose with a piece of tubing, and reset the code. Hopefully, it's gone for good now. Thanks for your excellent video and troubleshooting skills!

[@iamEddieP]

Never seen anyone explain things so understandably before on KZbin! Thanks

[@zackjalamani]

An excellent test, an excellent intelligent mechanic who explains things in a simple clear way. Thanks

[@madeyousquattopee]

Incredible. Watched a minute and twelve seconds of this video and wanted to go have a beer with this man.

[@csnr355]

I had a similar problem I changed egr valve dpfe and vacuum solenoid afetr all this i had coneccted the hoses from the dpfe wrong after correcting my error the light went off, but i did had a bad dpfe and solenoid i hope this helps. I am not a professional I am doit yourselfer. but learned thanks to guys like this. I had a 94 explorer xlt.

[@joemikos900]

As usual great video. You are amongst the top 5 professionals who also have the gift of teaching. I volunteer at my church's Car Care Ministry. Because of my experience I do most of the diagnostics. We don't charge anything and if the people don't have money for parts we often pay the parts tab. We have 5 lifts! On any given Car Care Saturday we may have 12-15 cars. All I have are basic diag tools eg multimeter, fuel pressure gauge etc. We do have an OTC Evolve scanner which is a blessing but not up date. I would love a scope. We don't have any subscription service either. I put a lot of pressure on myself being sure not to change parts unnecessarily as we have to be good stewards of our funds. Also it's just crazy to throw parts at a car that doesn't need them. As you know without the proper tools the diagnostics takes much longer and much more difficult. I have cancer so I can't work a regular job but I'm blessed to have the privilege and opportunity to help people and use my skills. I was an ASE certified mechanic but had to leave the trade. I was told I had 6 months to live in 01 but I fought back after spending eight years in bed...sorry for the long story but just wanted you to know how many people you help with your videos. I could never do what I am doing without studying the top You Tube teachers. Just like to add, if anyone would be interested in donating or loaning a scanner or scope or any tools it would be a great help and it would be tax deductible. We were recently on USA today and had 7 million views! Many people donated cars which we fix up and give away. We donated 27 cars last year. There is always a need for Diagnostics. Thank you very much

[@ogbranc]

Joe Mikos May God bless you.

[@joemikos900]

Brandon Corona Thank you very much Brandon! Even though I have been fighting cancer for decades, I still feel blessed. I have four great kids, a beautiful wife who stood by me while I was bedridden for about 8 years. People like yourself who offer kind thoughts help keep me going. Take care

[@shannonp4037]

Joe, I hope you're still working on things. May I suggest you start a youtube channel of your repairs. It could make the organization some much needed money to continue your great service. Also, you can link a patreon account for donations.

[@alleychange7008]

Would your organization help me?

[@dougdileo4727]

that is awesome.....

[@rickyhuff]

I've viewed many videos regarding identifying a rough idle and egr valves and dpfe sensors, but this one is the very best at how to proceed with workflow on solving the issue. Brilliant tutorial! Thanks!

[@realfixesrealfast]

Thank you Ricky, glad it was helpful. I appreciate you taking the time to comment.

[@JAKE3914]

This is a fantastic find!! Nice to have a mechanic that explains the problem in easy to follow instructions! Thank you!

[@michaelovitch]

That's very instructive. The great thing in your videos is the intellectual journey from the problem to the fix . Cool.

[@thewolf8848]

you gotta love this guy! he breaks it all down so you can digest it.

[@thePnoise]

This is a great learning tool video. Easy to understand, good explanations, lighting... etc. I'm a DIY mechanics for the easy stuff, but this video will help me a whole lot in understanding of how to fix P0401 EGR Check Engine on my 97 Ford Expedition. Good job guys. Keep it up and good luck with all your endeavors.

[@coronapizza]

You are good, professional, knowledgeable, educational the best of the best. THANK YOU very much for taking the time to help and add to the body of knowledge of the internet

[@GUNFREEKJR]

This video really is awesome, helped me on my ford ranger, good job explaining it and not just rambeling on like other videos. everything was very useful .

[@user-ju3od5gy5q]

Excellent video. I bet he has so much work that he has to turn customers away because he just cannot get to everybody in a timely manner. I think its called "highly skilled and a high degree of integrity"!

[@ChapmanJones]

Best explanation of P0401 I have seen. Thanks Chief!

[@Hurlburton]

Real world problems real world solutions. That's why I watch this channel.

[@seanwillman6373]

Same thing happened with our 03' Ford Focus. Would stall out at stop. Rubbed through on vacuum line. May be a common problem with this car versus buying a new egr valve. It can be that simple of a fix. Thank you for your video!

[@thomaselliott4562]

Excellent video. My 97 Firebird Formula LT1 had this problem. I tested and all seemed ok. On this engine the computer looks at the Manifold Absolute Pressure sensor for a 1 kilopascal pressure drop when the EGR is activated. On a hunch I removed the MAP sensor and cleaned the manifold port under it with spray carb cleaner with and without the engine running. Until I did this the flow code always came back. Cleared the code and happily it has not returned. EGR flow problems can be a challenge.

[@Jamar10]

Thank you so much for your video. I had such a headache wife daughters car, and your video showed me what was wrong. Cheers.

[@speedbuggy16v]

as a former tech, thats been awayu a while, thanks for the info on how to diagnose this problem. I have been studiously ignoring the wifes toyota for the last month with this code for lack of understanding of how easy it could be to diagnose. thanks cant see the forest for the trees

[@mmace8240]

great job and your way of making it understandable is terrific. I know what you meant BTW about chemistry and inert gases, Thank You so much for the education on the EGR and the associated fixes. A good technician like yourself knows you dont throw parts at a car to make it stick, lol

[@LuisCastillo-kz8vd]

Thank you, I am a mechanic that love fix and just replace if I don't have another option. I have the same problem with a 1997 Ford Windstar 3.0. I will post what I found. Blesses!

[@MrStockdizzle]

Your Videos are second to none. Thanks for posting.

[@johnmccarthy2268]

You produce the best videos on KZbin - thanks!

[@marlensands943]

A real mechanic and great job on the video. Hell if I lived close to you I would quite working on my car and bring it to you. Good Job

[@martystevens8357]

If you have vacuum at the EGR valve at idle, replace the TPS. It's causing the idle to increase some causing vacuum to be sent to the EGR. It can cause EGR position sensor codes.

[@myjournaltoahealthym]

Ok I had a Code P0403 pop up when I got my 08 Ford Focus looked at at the local Autoparts shop. Seems to be similar to P0401. I'll be checking mine this weekend thank you so much for the great video!

[@spelunkerd]

Great explanation, Duane. I guess I would have started with the hoses, as access to computer diagnostics beyond OBDII is not avail to a backyard mechanic. You make a great point that the pro needs to stay with basics, as the temptation would be to throw parts and see if the problem is fixed. That way would have eventually led to the solution, but only after the customer might have paid for replacement of normal devices.

[@TheLtrentlage]

How do vehicles without a DPFE monitor the exhaust to know the EGR valve is working? I have an ML320 diesel with similar issue but no DPFE

[@whatfayesay6607]

Hello, I just subscribed to your channel. I have a 98 Dodge Grand Caravan 3.8L, and it's that time of year again. "Smog Test". My check engine light is on, it has a rough idle, and my gas millage sucks. Code P0401. My mechanic suggest I pass my test under the radar, as apposed to cleaning out, or changing the EGR valve or possibly worn out vacum hose. Oh, this is the kicker, sometimes my dash gadgets don't light up, and the car will turn over, then immediately turns off. I hit the top of the dash board before turning the key, this worked a few times; but lately, I have to call a tow or leave it there until the next day, then it starts up. Could all of this be due to my EGR valve or do I need to replace the ECM Control Module? What are your thoughts?

[@KeyWestBluesX]

excellent video amazing these are available. I just want to chime in that sometimes they are quick to say "do proper tests--don't just throw parts" but the truth is when you go in you sign your life away on a big contract and it can be a couple thousand to get the vehicle back. The only people that can do true testing are highly skilled and using expensive equipment. a few minutes of their time and for a fact you are already up into the hundreds. now to avoid losing those hundreds---you have to sign your life away hoping it fixes it. That's just the facts of life.

[@LONKOLD]

Great video but what is the part number to the vacuum hose from egr solenoid to the intake manifold that you changed? mine was the same on my daughters 2004 Ford Focus and again great video

[@canadapainter658]

I got a Ford Tempo GL 3L V6 and I just changed he EGR valve and still the code pops up insufficient EGR valve flow...Do you think I mismatched the hoses? the is one hose,,, I am not sure where it goes...

[@ronaldoquintos1675]

My problem is more complex. Toyota Prius C 2012. I cleaned passage already so no question about that. I used scanner to open egr engine stumbles really bad so obviously no restriction either. I checked MAP sensor measure voltage etc, it’s functioning properly because voltage fluctuate with different amount of vacuum. The only thing I can think of is computer is somehow causing the trouble code maybe it needs update or even another computer. I have yet to see a solution Identifix did not help me either. By the way I am not a novice I own a hybrid / EV repair shop so I’m pretty advanced in diagnosis but just this one has been nagging me for a while. Also it’s my personal vehicle with 360k miles on it

[@jimmy101112000]

@jimmy101112000 the exhaust if you hear loud exhaust noise that pipe is clear. If its plugged it will usually be full of hard carbon. You should be able to squirt some ATF fluid into the EGR port to clean and break down the carbon which takes some time to soak if you can't get the carb cleaner to work. I recommend a a stiff flexable wire to help unclog it. I had to do this on a GM 3100 engine and its port was clogged with rock hard carbon. Carb cleaner and 20 mins of poking and spraying.

[@djmajiktuch82]

I did a vacuum leak check on my 2001 ford ranger 3.0L v6 with smoke and I ended up getting three leaks one was the egr valve the other was the iac valve the last one was a small hoes. I took off the egr valve and the diaphragm was holding vacuum but it was very crusty with a lot of carbon. so, my question is why was there smoke coming from underneath the diaphragm housing any ideas?

[@alb12345672]

If you dont have a fancy scantool you can disconnect both DPFE hoses, and draw a bit of vacuum on the DPFE (maybe 5 Hg or so)and monitor its voltage using a multimeter or scantool. If there isn't a linear relationship(voltage jumps around) the DPFE is implicated. Remember the DPFE is measuring the difference in pressure between the two ports.

[@jimmy101112000]

@mrfordexplorer97 Sounds like you got a plugged port. To check there is two ways. One is to pull the vacuum line and apply vacuum to the EGR while the engine is running. If it stalls the port is clear. If it does not stall the port is plugged. Or you can remove the valve and plug the vacuum line start the engine to see if you got great suction on the intake side of the EGR if you don't the port is plugged. Use some Carb cleaner and a stiff wire to clean it. The other pipe runs to

[@peterjensen7533]

Clear, specific knowledge, thank you!

[@robbyjones7631]

Check for vacuum at idle. If so, replace the part responsible for vacuum to the EGR. If the engine smooths when you unplug the EGR, it's NOT the EGR. If the engine continues to run rough with the EGR hose disconnected, it could be the EGR. Remove it and check it. Hook up a Mityvac and pump it up and see if it holds vacuum. If not, replace it. There should be vacuum at part throttle but not at idle. A broken hose can cause no vacuum. Don't hook up a hose directly to intake vacuum. It'll cause vacuum at idle. A Mityvac can be hooked up to one end and plug the other to see if it holds vacuum, which it should. Block off un-necessary hose connections to test it.

[@patriotkennethburlingham7059]

Nice video. My connector to the DPFE sensor broke and I had to replace it but I am not sure if I spliced the wires back correctly. I know the middle is the ground but the red wire and brown wire not sure of the pin location. Any help would be appreciated. Also the new plug wiring is not numbered or color coded. Ken.

[@TzzX78]

What type of diagnostic equipment was that? It's sure helps to fix the car the right way. And avoid buying unnecessary parts

[@HighestRank]

It's a dealer-level scanner. About $900

[@Usmanthemecano]

I think the quickest way is to check for voltage at the dpfe key on engine off. Should read about half a volt. If not go ahead and replace it

[@PIANOSTYLE100]

Sakeenah Auto Solutions from what I've heard they can be ohmed out with aresitance tester. Also I think they all run off a 5 volt reference.

[@Davy87nj]

Good video, going to start working at a new shop with possibly more diag in my future as a tech. Thanks for the before and after on the dpfe pid.

[@jeffreynelson2660]

Sir: my 2001 Expedition has the check engine light on, same code, insufficient flow. Will it hurt the car if I wait for warmer weather to track down the problem?

[@johncouroupacis9603]

I enjoy your work im always learning 30 years into it

[@matthewliggitt6402]

I have a ford ranger 2002 and checked the flow and it stumbled, so solenoids working? and DPfe is bad?

[@MrLeal1015]

i like this kind of explanation , it is very clear and understandable i really enjoy to see these videos. they are very helpful.thanks.

[@bmb49]

Thank you very much for the video and information, I've been try to fix this for a while but this may be what's causing my issue and just the info I needed thanks

[@greggyfree]

Best explanation i've seen. I wonder if that car also had a high idle when it was cold.

[@shakeeloniel8891]

Great machanic thanks for sharing. my problem was a leaking gasket on egr valve.

[@realfixesrealfast]

Glad it helped, thanks for your comments.

[@fixinggrace]

@920gamez You probably did this,but check the plumbing from the engine, the canister purge solenoid and the canister itself. Also check the cas cap. P0445 means a large leak in te evaporative emissions system. I had a similar problem with my Dodge and it was a loose hose.

[@djhitman323]

I have some codes on my 1999 cougar v6, and I'm getting the p171 and p174 codes, and after tune up and intake gaskets i have narrowed done to egr system fault. I hope these tests help. Any suggestions? Also failed smog because of high nox...

[@rubenfilippus2956]

I have the Isuzu kb 300d teq 4jj engine and its not starting. Some Times if it starts it's noizing in the terbo.and when i put it to the machine to diagnose the problem it tels me EGR valve bank very low.is there any way to clean it without replaced it?and if it's soo which tools and spray must i use to clean it?

[@Rosman1974]

i have a 2000 ford f150 and i have the same code. I changed the egr valve but still have the service engine soon light on. the mechanic wants to charge me $160 to clean the system because he feels i have a blockage. He mentioned a sensor but I don't know what he meant . Would like some feed back

[@tracyjohnson3326]

i am looking for the part numb er for the vacume line he replaced mine bad as well, i cant it any where.

[@johnmazza9432]

I just watched the first minute or two of your video and I have a question. You say that recirculating carbon that wont burn back into the engine will lower the combustion temperature which makes sense , and it will lower emissions , which makes sense because nothing is burning. but if nothing is burning and generating a release of energy, then how can that power the car ? It sounds like the system might as well be putting water vapor or peanut butter in our engines .

[@tigaspinoypower]

Sir! I bought egr valve but aftermarket do you think this is ok? What im planning to do this weekend is to clean my MAF,IAC AND EGR and im confused which spray do i have to use not only the parts but also the passeges. Is it ok to buy aftermarket parts? just in case some of this parts does not work. Please help ...Thanks!

[@felplayvina]

great info about EGR system really clear thank you..

[@puntoochoracing82]

I have the same code for my toyota camry thats good info...Now I'm going to check it out. Because the EGR valve for my car cost $150...DAMN!!! =(

[@supersesqui]

Nice presentation. logical explanations. Good simple background information on fault. Clear well lit video. Easy to listen to and follow. Thanks for your good work.

[@producedbydoeselo2293]

You taught me exactly what I like to know.

[@guidosalas7089]

Excellent! thank you for sharing your knowledge.

[@yuma310]

Maybe the parts manufacturer placed the tag on the vacuum hose purposely to prevent the same tube rubbing failure problem.

[@jcheathamm]

Could the Dpfe cause driveability issues that occur with the p0401 code or would the check engine light be the only symptom of a bad Dpfe?

[@machia0705]

Can you help me out ? I have a 1997 Ford Expedition with a 4.6 V8. My engine continues to show a egr problem code. I replaced the pressure valve, EGR valve and solenoid . Is this a leak in a hose or could I have a dirty intake manifold ? Thank you in advance from New Jersey .

[@realfixesrealfast]

If you have replaced those parts then you most likely have a blockage in the ear passage way, likely caused by carbon build up.

[@machia0705]

realfixesrealfast The rear passageway ? Would that be the egr tube going to the exhaust manifold ? I have plenty of vacuum on the intake and all components that I put in check out. I also show an evap large leak and I found it. Will be fixing that today. Leak at vapor canister. Could that be related ? Thank you for responding

[@strokewarrior5762]

@@machia0705 no, it would most likely be the internal passage way in the I take itself. It ca usually be cleared out with a small pick and/or brush

[@machia0705]

My Stroke My Recovery I have vacuum on the intake.

[@PyramidLilly]

hi I have to tell you first you are thee best I have seen! I have a problem and changed the EGR valve and the O2 sensor still have the check engine light on and code is p401 101 have to get this car to pass NYS vehicle inspection this month please help me to check where I go to get such a mechanic like you !!

[@takealready]

Thank you so much for educating me. It helped me understand what's going on.

[@brunovilleneuve]

Thanks a lot for this instructive video. I'm not good in mecanics and this helps me understand some new stuff about EGR and troubleshooting :D

[@nickturner8105]

Excellent work, clear, precise and accurate. Thanks.

[@cesarcelestino1098]

I have a code P0402 on my Miata Excessive recirculation gas detected. Would it cause the engine to run rough or stall? My car runs fine with the cel on.Bad signal maybe? Any opinion

[@Purowalangkwenta]

I have a 2010 prius and light came on. I bought a scanner and it said P0401. Then i erased it then the light came off. Is that ok? Because i need a smog before i register the car. Thanks a bunch Chris

[@yannkaloustian2913]

Top notch Sir. Very helpful.

[@jasont1917]

That's the real deal. 75 dislikes... the other mechanics don't like him teaching you how to do it yourself. Taking money out their pockets. You can also test with vacuum pump and voltage meter.

[@gjholcomb]

can I pinch the egr tube closed or use a blanking plate and eliminate the valve altogether?

[@4arocker]

My 1999 Ford Taurus (Duratec engine) would go through a new DPFE sensor about every 18 months. Just like clock work. It wasn't so bad as i could pick them up for about $45.00 each from Autozone and the work would take about 15 minutes of my time.

[@mariesepich7557]

very clear, concise explanation!

[@TheGeohart]

will a bad egr vacuum regulator cause high idle, when the engine warms up

[@weber247]

Like carbon deposits in the EGR ports ?

[@arvindtaylor6871]

Cool video. Your explanations are great as always.

[@hannahirvin7873]

Excellent explanation. Thanks!

[@hullcanada]

Can make a video using a 1992 FORD TEMPO 3L-V6?....I got the same "insufficient EGR flow detected' code....I already changed the EGR valve last year just to make sure it is new.... and now I got a code 332( OBD1 reader)....

[@richwaianae1]

Excellent explanation of EGR flow. WOW

[@sarahbelle81]

Wow. Best video ever

[@joseph2323]

so if my dpfe has no hoses on it as the plastic broke that holds the hoses this code would arrive ?

[@fixinggrace]

It's the cast metal sensors that have a high failure rate. The composite ones are a lot better.

[@mrcrazy3872]

yea but what do u do if u don't have those gagchets I put a new egr vavle and line evap system caniter and sensors under my car by the gas tank help still low gpr flow saying tester, this is a hand tester and wont passs emmisions 5 years trying everything ,thanks

[@HighestRank]

There's another sensor on top of your gas tank on the mystery machine.

[@02lowrider62]

I had a dpfe sensor melt and it was caused by a clogged cat! It was on a 03 ford E250 with a 5.4L motor. Be sure to find reason cat went bad mine was bad coil packs.

[@LAISLA23]

can you yell me how to find the problem on my 2001 town and country , p401 i replace egr valve , it had warranty ,replace down stream o2 sensor and clean tube connecting egr to intake , tube its clear and port where egr mounted to block also clean , i use a vacuum pump to the egr vacuum port and egr move up and down , but no engine stall , i command using scanner to do flow and to block flow and no change , i remove hose coming from transducer to egr valve and no vacuum ,but little plastic hose from intake to transducer has vacuum, so was the problem? please help i feel like some kind of exhaust leak somewhere ,

[@realfixesrealfast]

I can understand your frustration, Someone really needs to look at your vehicle in person to see the results of testing. I would be actively monitoring both the STFT & LTFT while testing with propane tests. You may have a constant air leak that is making the results of your test. If you add propane , the STFT should react to it and help you find it.

[@MightyJoe0429]

Love your videos! I think I have watched ALL of 'em!

[@fredhandy2063]

Great video! Thanks for sharing.

[@pablogomez7519]

Would a bad Egr valve cause hesitation??

[@My68Tempest]

Excellent video. very well explained

[@im2real]

So basically you won't know the problem till the sensor and the value is working? ( But) Even then your not clear. My question is when you have both working will it then tell you exactly what the problem is, or if there's a problem at all?

[@blancacortesd7]

by replacing egr valve will it stop it by motor vibrating

[@Gonzoe714]

Great video thank you

[@tukamote6185]

These is what real mechanics do ladies and gentlemen and take his advice if you a diy and of course don't be a parts guy

[@denyss7280]

Excellent video! Thanks