Fuel Pressure Regulator Diagnosis + Understanding (HD!!)

[@joewahrerMotorcycleMan]

8 years later we are all still benefitting from your video...thanks!

[@EricGonzalez-bd1qd]

9 years later ;)

[@xmalcom8198]

I've been a mechanic for 35 or 40 years he's the only man that could explain to me why a fuel pressure regulator should be behind the fuel rail I always thought all my life the pressure regulator should be in front of the fuel rail thank you sir you are absolutely brilliant!

[@SchrodingersBox]

Thanks for the comment! Yes it makes sense when you “see” the mechanism doesn’t it!!

[@olenaerhardt7725]

If the Fuel Pressure Regulator is inside of the Fuel Filter (e.g. PTC PGF846 Fuel Filter), it will be in front of the Fuel Rail. So the fuel goes from the Fuel Tank through FPR+FF Assembly (Fuel Filter and Fuel Regulator in it inside) to the Fuel Rail. So you were correct for the Fuel Filters w/FR built inside.

[@mkwlsey79]

Truth!!!

[@mkwlsey79]

Truth!!!

[@danieldoll4721]

Best there is

[@brandonhedges719]

I know this is an older video but not only did it help me understand a FPR better but the entire process involving fuel travel in a vehicle. This helps troubleshooting tremendously.

[@jawadurrahman8659]

I am not a mechanic professional, but I love to listen to your lectures without any need..

[@chrish3720]

I knew all of this but, your explanations are so much better than mine that I often tell my customers to go home and watch your channel. They usually return as experts on the particular problem with their vehicle. It is fun to have them tell me how to repair their own car. Thanks man. An informed customer is a happy customer.

[@jodyroberts9027]

I am a do it yourselfer; and by no means a master mechanic and I think this channel should be a must for any body

[@itsjiraheta]

First off, I want to thank you for the taking the extensive time to explain this. I happen to bump into your video trying to diagnose an issue with my idle. You have made me a little bit smarter today. Thank you.

[@SchrodingersBox]

My pleasure! Thanks for watching

[@johnd942]

This was an impressive presentation all round. Video, rate of speaking, clarity, emphasis on key points, and logical steps could not have been better. In fact, as a retired automotive trades instructor I felt a bit jealous. So well done in every sense of the word! Cheers!

[@SchrodingersBox]

Wow, thanks for the compliment!!!

[@ronniewoods2155]

Totally agree - have been watching several videos and all are excellent.

[@garryhallmark7154]

Garry. I recommend this video to the people who want to know more about fuel efficient cars.

[@whocares2227]

@@SchrodingersBox So, I've been a automotive and heavy equipment mechanic for over 45 years and consider myself to be very good and always do top quality repairs. You have to have a good understanding of how things work to produce quality work and not just be a parts replacer. I think your explanation of the fuel system is top notch. Keep up the good work.

[@hp2179]

You forgot to drew the fuel filter for the dirty fuel.

[@donkline8600]

As a former high school auto shop teacher, before the advent of fuel injection, I deeply appreciate you video. I tried to instill in my students that knowing how something works you can better determine what is wrong and fix the problem at it's source. Thank you very much for this video.

[@abderrafikbelal4990]

8YEARS after, and it's always the best corse concerning fuel pressure regulator that i found it in youtube. many thank's

[@SchrodingersBox]

Thanks so much!! Yes between this one and the fuel trims video (also 8 yes old) those alone cover almost 70% of car issues right there.

[@stephen6945]

Hey Matt, you've made a huge impact on my understanding and overall approach in the past few months. Starting to feel way more confident in my diagnostic capabilities.

[@aaronrodden8121]

2024 and a 2012 Suburban later, we meet again Boss Man!! I COULD not remember how to find you or your videos and by the grace of GOD I came across this video!! I remembered that you teach not only how to replace parts but more importantly WHY to replace it, how to know its that part and an intimate knowledge of how said part works!! You are the mechanic/tech that can honestly say you are GREAT at what you do because you honestly KNOW what, where and why you are doing what you are!! This is knowledge that should be just as important to pass on and never let die as anything I have ever seen! This technically makes you a legend! At least, you should be! No B.S., nothing but just legendary!!

[@SchrodingersBox]

Hahaha thanks- you are too kind!!

[@gordonfirth7254]

Hi, thank you so much.. this fixed my problem after I tried everything else. 10 minute job and no cost. My 1990 Foretravel Grand Villa 460 gas pusher had been sitting for some time and I made a 200 mile trip with to working so bad. The diaphragm in the FPR was stuck at the bottom,removing the vac hose made no difference in the rough idle so t sprayed penetrating oil in the vac hole on the unit and applied high vacuum with my pump and it pulled it loose. The engine instantly worked perfect. Without this video I would still I would still be lost. Thank you so much and I will be enjoying my trip back home because of you. :) Gordon Firth, Nova Scotia, Canada.

[@1chance4life76]

Gordon Firth nicely done and good advice for a quick fix on the FPR!

[@pbee6644]

Great, logical presentation. When I was in school the best teachers (especially math) taught you to think, reason & solve instead of memorize (or follow confusing, lengthy flow charts). As a retired tech (20 years ago) - actually we were still called 'mechanics,' I thank you for bringing me into the 21st century's fully computerized world. When I retired we saw few OBDII systems in private shops, so you really got me back into the analysis mode for which I'm grateful. I'm currently trying to resolve an intermittent problem- the worst kind- on my 4.6L '06 Grand Marquis (old guy's car) throwing trouble codes P0193, P0171 & P0174 while the car runs flawlessly- except for the illuminated check engine light. The pertinent freeze frame data is RFP @ 75.99 psi-which scares me- and LTFT @ 29.7% on both banks. After watching your above video & the 2 on understanding fuel trim, I'm going to retest concentrating on the P0193 which looks like the real problem area. But testing so far- especially after clearing codes and (temporarily) bypassing the pressure regulator- shows everything within normal specs @ idle, 2500 & 1500 rpm's. My inclination is to repeat the disconnected regulator tests, now that I better understand the systems, then block vacuum to the interior accessories & carry on from there. However, since the car runs so well and this being the elusive intermittent riddle, anything you care to contribute would be ever so much appreciated! Would you consider the RFP value dangerous (it's 39-40psi in all tests)?

[@pbee6644]

+Pat Bbb Here's some clarification on my post a day ago and after further testing. The high fuel trims in freeze frame given were from when codes P0171 & P0174 appeared. Currently only P0193 is coming up intermittently and the LTFT readings in that freeze frame are normal. In fact the lean fuel readings haven't reset codes since pulling the vacuum line from the FP sensor while testing the fuel pressures. The repeated tests now convince me the problem is/was a defective fuel pressure sensor, which on my vehicle is a sensor only (on the fuel rail), not the regulator. and I've replaced it. My assumption is the 75.99psi RFP is actually a low voltage measurement showing 'pressure' at the extreme high limit, but not true fuel pressure. Time will tell if my diagnosis is correct. Matt, I hope you'll see my posts and respond with some further input & info for my 'schooling,' especially the upper fuel psi limits. Also, where is the actual pressure regulator(s) in the 2006 Grand Marquis. I'm guessing it is the unit mounted on a bracket on the passenger side firewall with fuel supply lines in & out. But the out line goes to the throttle body, not either fuel rail. And is there another regulator/control in the gas tank as shown in the parts catalog?

[@cobraninetysix3883]

Great Video Matt! I have been working on cars and motorcycles for years and have taken automotive coursework, your videos certainly meet the mark. You have an ability to communicate the technical in a way that makes it easy to apply in the real world. My favorite is diagnosing fuel trims! Anyone who watches and waits just to call you on a mistake or slight error in communication obviously doesn't understand the purpose of your channel. Please keep em coming!

[@jameshollingsworth3214]

absolutely awesome presentation. replaced fuel pressure regulator and got vehicle to start but still running rich. I know where to start looking. Thank you!!!!!

[@SchrodingersBox]

Thank you! if vehicle is running rich you want to start with a fuel trim analysis at idle vs load. this will give you a better indication of the cause.

[@theadventuresofbellaandjos6435]

Your videos are longs, but they worth gold every minute of it, knowledge is what make a man wise, thanks for sharing your videos, i being having a rich, and have change all the sensors you can think, and maybe this is where my problem is.

[@theadventuresofbellaandjos6435]

Update on my pressure regulator, tested it and the needle jump all the way to the max reading on my presure tester 100 psi, order a new pressure regulator, and readings are now 45 psi, problem fix, thanks again thanks to your video i fix my car, i didnt know that a bad pressure regulator can bring u this problem and alot more.

[@billsmith2212]

Matt : thanks for the lesson . I was driving my 1987 Chevy Celebrity 2.8L , it lost power and stalled . I pulled over and no restart . I had a strong gas odor . It wasn't White Castle . The gas was running out of the throttle body . I traced the vacuum line to the FPR . I put on a vacuum pump and it immediately pulled gas out of it . The diaphragm was ruptured . There is a vacuum junction on the throttle body . The FPR line is there . That's why the fuel ran out of it . The FPR is buried under the intake plenum and mounted between the fuel rails . It is not a simple replacement . I changed it and the car runs fine . Keep the lessons coming . Thanks !

[@alberthamilton5408]

I don't know how your channel came up on my feed, but, I am thankful that it did, Thanks again for another great video.

[@yarduengo]

Very well explained.I'm an RN, but I love to do mechanic DIY to my cars and my family. Good job explaining how the fuel system works.

[@filibertomorado740]

Thanks for an excellent explanation of the FPR, I now have a much better understanding of how it works. Being a complete novice, I now feel much more confident when discussing this with a professional mechanic. I will have the testing done because my Jeep sometimes has a hard time starting when it sits for a while. Keep up the excellent videos and excellent explanations; they're invaluable to us novices.

[@The130Loadmaster]

I worked on Jet Engines in the Air Force. It was far easier than working on cars. We had fantastic instruction and fantastic documentation to perform maintenance. Nothing was ever a mystery. Finding good instruction and good documentation on the plethora of different vehicles is much more difficult. Your explanation on this simple system has made my backyard project a snap. Thank you

[@SchrodingersBox]

I guess jet engines don’t have to pass emissions lol.... or maybe they do?? I am curious about that now that a i think about it!

[@briand9513]

Matt, your videos are very intelligently done. Easy to follow and understand. Thank you for sharing all your troubleshooting knowledge. I learned a TON from your fuel trim videos, and now have a much higher understanding of how trims work. Now working to put it all together with more of your videos -Brian

[@MD-173]

So good I watched again. Let's do a sequel titled "Fuel Pressure Regulator Diagnosis + Understanding Returnless Fuel System".

[@franciscoperna7963]

Thank you so much Mat I am now one more of you fans, I have watch the fuel trim explanation you gave and I realize I been doing things THE HARD WAY all this time I love mechanic work. I started watching u-tube and I notice most every one check the fuel trim to diagnose the problem , so I check to see how it works and that's when I ran in to you . yep am a idiot lol but not any more thanks to you sir all of the sudden now every thing make sense. I cant wait to get back home to my shop pull out my foxwell 630 pro scanner and find out my low end power lost problem on my 2004 GMC. Coming out of a dead stop I have nothing but after she hit 1500 RPM HOLD ON TO YOUR SEAT because she comes a live. thanks again and god bless you.

[@Blutnase]

I once had a bad FPR leaking fuel through the diaphragm which I only stumbled across looking for vacuum leaks by sucking on the hose. Blech! The problematic symptoms varied between immediate start (one or two cranks) when hot, and extensive cranking when cold. These symptoms made sense after the fact, but I was incorrectly imagining the actual function of the FPR until this video. It did not occur to me that low vacuum meant higher pressure. My incorrect "assumptions" were compounded by my other misconception about vacuum under load! You are right -- now that I understand the proper functionality I am empowered to work on this system. Thank you for taking the time to share this!!

[@SchrodingersBox]

Yes I have seen this many a time. I usually diagnose it immediately with fduel trim analysis. It's especially common on theose GM 4.7 and 5.3L's- they leak internally making it really tough.

[@chucksterhanna5060]

This guy is an awesome teacher. Looking forward to checking out all of his videos

[@johnsoper7649]

for learning opportunities you present I am very thankful and grateful.

[@eduardorivera421]

Love your patience bro, I get it now, love the way you explain things, the hardest thing is to diagnose but when you know how is supposed to work, is walk in the park, thank you bro💪💪💪🇵🇷 wisdom is knowledge, and to know there is power. 10 stars bro.

[@armanddeperdussin3897]

Excellent video! You took great care to explain the fuel pressure regulator -- and without a jiggling camera.

[@SchrodingersBox]

Glad you enjoyed it!

[@electronpusher604]

The "understanding" point you make is so damn true. True in chemistry, math, physics, everything. I just started learning about cars a few months ago, and I can diagnose so many things already just by thinking about it. Such a shame the schools seem to push the opposite point of view.

[@rebel.mma.youtube]

Hello. The subaru wrx fuel injectors are in series. The regulator I think is before 3rd injector. My question is how does one know if fuel goes into the last injector if the regulator is befire the 3rd Injector? Hope my question makes sense

[@geryloftis7985]

I have never known anyone who could do an in-depth diagnose on a vehicle system without putting a wrench or some type of tool on the car. Impressive.

[@lozanospain1]

Crystal clear explanation,you deserve half million of subscribers more,this channel is Gold . Keep it up with this helpful and interesting channel. Greetings from a Mechanic 👏.

[@jogalong]

I salute you for the ability to explain things. Thank you!

[@LongLe-xd4jr]

Thanks for explains the operation and function of the fuel pressure regulator .

[@spelunkerd]

With so many sensors in modern vehicles, it's refreshing to see a simple mechanical feedback loop, seemingly independent of electronic control.

[@SchrodingersBox]

This is a good point actually, I hadn't really though about it! It's about the only mechanical, non-electrically controlled component on a vehicle lol. Anything else- EGR, AIR, etc at minimum uses electric solenoids to open passages and allow vacuum but this is just direct and simple.

[@trealwilliams1563]

Man... I call you Mat-The-Genius... You know a little about a lot of everything!!!

[@billbyrd9845]

I'm an old man. When my 55 Chevy would struggle to pull up a hill, my windshield wipers would slow down or stop. Ask your audience to explain that one. Great video.

[@SchrodingersBox]

What’s your voltage drop on the battery? I’d start there.

[@billbyrd9845]

@@SchrodingersBox I see that you are too young to know the answer. Wipers in those days were controlled by vacuum. Gotcha!

[@SchrodingersBox]

Lol yeah you got me there. I never heard of that in my life but I looked it up and you’re right. Yeah i pretty stick with stuff after 1996 for OBD2!!

[@estrelladelnorte1308]

I like that you accept that you could make mistakes and people could point at it , no one is perfect and we ALL make mistakes , that's how we learn .

[@royeutsey1]

Doing work on a 2001 Nissan Altima. I am a diy, just changed a fuel pump for the second time. Wanted to understand the fuel system more. Will watch again. Thank you

[@SchrodingersBox]

If you are changing a fuel pump twice within a year you are either misdiagnosing it, failing to catch a voltage drop or other electrical issue, or you are not cleaning out the fuel tank and replacing the filter before replacing the pump,

[@MrWolfsbmw]

Thank you for giving your time to explain in a way everyone can understand, it was generous of you. I'm about to cover fuel trims and engine management in level 3 in college and it helped me understand a bit more of what's actually happening to my car currently. A new regulator is on its way ;)

[@jtg2737]

I think I just found my problem with my Chevrolet Silverado 1500. I found a good crack on the 90 degree rubber connection as part of the hard plastic hose on the vacuum side of the fuel regulator. What was happening on my vehicle is that right at the moment where I wanted to accelerate there was a slight misfire/hesitance/stuttering if you will. The symptoms led me to thinking that more than one injector was dirty, fouled spark plugs or that a spark plug wire was grounding out. However from the looks of it, no. Your explanation starting at 06:39 clarifide in my mind how the vacuum works at idle and too immediately what is happening with the vacuum pressure right at the moment when one accelerates. GREAT explanation! THANK YOU! THANK YOU! THANK YOU!

[@weimarutube]

This is a very nice video! Thank you for taking the time to assist us shade tree mechanics

[@queashepapa3466]

for me, the best fuel system tutorial on the web ever, easy to understand, great draws and perfect explanation, thank you very much

[@milesghoover712]

Excellent explanation of how a fuel regulator works! Thanks and keep up the excellent tutorials!

[@toddcrumpjr3567]

Jeez, people have nothing better to do than to nit pic you. Screw them, I like the vids it's nice to hear functionality of things from a fresh point of view. Great job man! Keep up the vids if your still at it. I know this vid is 8 years old, but still getting views.

[@SchrodingersBox]

Much appreciated!!

[@user-dx7gh8qi4o]

I really like your videos Matt! Your a great teacher, you should teach automotive. Don't even think about wasting time on the negative people's comments. They are jealous that you know what you are doing and you also have a very successful KZbin channel. I don't see them posting up videos of how to fix things. Keep up the great videos, we all love them!

[@nandanalal5072]

Your teaching is not for the engineers but normal technician like us all over the world

[@SchrodingersBox]

Thanks! That’s what I aim for- to keep it understandable by the mainstream.

[@freemanwang]

best video on fuel pressures, hope more vids come out in the future.

[@jerbburleson1]

Thank you for these theory type videos. It really helps the occasional mechanic who can't really afford a good mechanic nor the diagnostic equipment. Imagine Beetle Bailey in the field, it is relatively important that he has some idea how to fix things.

[@SchrodingersBox]

Beetle Bailey ROTFLMAO!!!! now there is a reference I have seen before lol

[@ignacioromero5014]

Every tid-bit of this - is stacking mental gold bars, Thank you... you are making a difference.

[@johncooper7242]

this is a really excellent tutorial. Finally .....at last...after years of partial insight and despite having the Bosch manual and various other manuals, its the first time that I have completely understood this aspect of the fuel injection system operation. Once you appreciate exactly how the engine vacuum together with the FPR control the fuel rail pressure and delivery, engine performance then becomes a diagnostic tool , pinpointing fuel pressure and delivery issues. thank you

[@danieladgate5065]

Very educational...so much covered and it really allows understanding for the mechanics!!!

[@artienet]

Excellent Video! Well, as one saying goes.. " You Never Stop Learning".. It's unfortunate for me that after all the years I actually believed the higher idle would create more vacuum at the regulator.. lol.. Thanks for all the great info and video. It's Appreciated!

[@ghanimalkuwari5090]

Once again a flawless job in explaining complicated systems ...amazing !!!

[@simonbelson4503]

Hi there from the UK. Thanks for an informative video...my mk 2 golf has the issue of fuel being sucked through the vacuum hose, I thought it was the FPR and watching your video has not only made my understanding of fuel pressure clearer, but confirmed my suspicions..thanks once more.

[@TheWalterHWhite]

Hey matt! love the channel and I very much appreciate the level of professionalism, knowledge, and comprehension you bring to the table. On spot with the understanding and diagnosis line. It's a shame that people would rather see how to fix something rather than why it needs to be fixed, why it failed, how it works in harmony with other systems, an how the actual component or system works. As you do, I am also always stressing the point of diagnosis and comprehension of automotive systems. I shake my head way too often when trying to argue with the wrench monkey on the finer points of thorough diagnosgics. Keep up the battle between the informed and the ever so oafish parts changers!

[@SchrodingersBox]

+Mark B Thganks for the encouragement! Ignorance MUST be challenged if it is ever to change !

[@CharlieCiampa]

Oafish?

[@lodhiautos9761]

Thanks for taking the time off your busy day to make such a nice video tutorial on the fuel regulator and the fuel trims.

[@SchrodingersBox]

My pleasure!

[@kanagarajkanagaraj6775]

very good explanation about fuel pressure regulator. I just started learning about cars a few months ago from my native south INDIA. detail and mathamaticaly good tutorial. keep it . thank u.

[@rgmeyers66]

Theory, then practical followed by a summary. First class! Many thanks.

[@SchrodingersBox]

Thanks for noticing- that’s the exact formula I try to use!!!

[@billthompson9595]

THANK YOU VERY MUCH FOR YOUR TUTORIAL! Extremely interesting, I learned a lot. Every thing actually made very good sense.

[@urnzwayzmoove]

Thanks for making this video 9 years ago!

[@buddyfrederick121]

Matt, you rock! very thorough explanations reinforced with live demonstration - you have A GIFT, sir. Please keep churning out the videos!

[@charlesdowns1691]

I appreciate your classes+ you make things much more understandable. also I realize after the book work on auto repair or classes which I really enjoy + next comes hands on and training which is more understandable with a good teacher. I really appreciate.

[@SchrodingersBox]

You're very welcome! Thanks for taking time to let me know!!

[@edwardfourie9409]

the way u explain it makes me even want to learn more thanks for posting this video

[@hackingthematrix1141]

Jesus!! Thanks again Matt.. I'll try this on the hopes that it fixes my issue. I can't get rid of the rough idle in my Modular 4.6 4v. Now it is getting worse. Something is preventing the engine from passing 2000 rpm unless I press the accelerator harder to get more power out of the engine. Under this condition, the ride is rough and the gas mileage drops to a horribly 10 mpg. I changed the fuel filter, all three cats, cleaned the MAS sensor, changed the throttle body sensors, the air filter, spark plugs, coil packs, checked for vacuum leaks .. I know what you're saying right now but I'm new to your channel and don't have a diagnostic tool to check the fuel trims.. just went to Autozone to get a reading which only told me that I have a misfiring on my number 8th cylinder..

[@SchrodingersBox]

I usually start with a basic fuel trim analysis on symptoms like that to at least get a definitive direction.

[@thomaselam6006]

Great job explaining the system operation! Thank you for taking the time to make this video.

[@stewartbruce2409]

You truly have the gift of a great communicator and a teacher. If I only had instructors with your ability schooling would have been much better, and enjoyable. Thank you for an excellent tutorial and keep up the great work!!!!!!!!!!!!!

[@SchrodingersBox]

Thanks man! Happy Thanksgiving

[@djgeo24]

Exelent video thank you so much, u are the best teacher ever.

[@fieldsofomagh]

A general list of maintenance friendly cars which would include amongst others,a schrader valve on the fuel rail,room to service,front location for starter motor,alternator ect,and a proper workshop manual included, would be great.Great video and easy to understand.

[@SchrodingersBox]

And don't put the spark plugs under the plenum, God I hate that SOOOO much for so many reasons !!!

[@techsavantlove]

Tom, A 1970 6 cylinder Chevy pickup would meet most of those requirements! You can even change the spark plugs without damaging your skeleton. I miss the old days.....

[@johng.4959]

Thanks for the excellent communication and video!

[@mpt117]

I’m 5 minutes in, but I’m pretty sure this is the series I’ve been looking for, I’ve struggled to grasp some automotive concepts but your right. I’ve we can learn to understand the major components then we can learn to diagnose our own cars issues ourselves rather than taking pot shots. This will hopefully help me Fix my Prodrive v7 Subaru

[@SchrodingersBox]

The other series you are looking for is my fuel trim series- it's even better and more universal. I use fuel trim to even determine if fuel pressure is a viable possible variable

[@MrSnapper1d]

That is very good explanation on fuel regulators.

[@johmu5466]

Extremely well described Re Fuel Pressure Regulator Diagnosis + Understanding...! ...Feels like I learned the whole subject (principles and practical hands-on example/s) in an extremely short period of time... will definitely help in diagnosing fuel systems... Thank you !!!

[@husseinhassoun7232]

Very helpful, and I appreciate your explanation of the concept, it was very nice. Thank you.

[@petemoss9693]

Great Video - this lady really lucked out big time also you having to help her out is a good jester - something as a simple radiator cap people don't think of replacing . Once again you did a great job .

[@infinityguy829]

Thank you, that was very clear and easy to understand.

[@teagar3]

GOOD Video - wish there more videos like this one. Should note, on most GM vehicles that if the diaphragm in the Fuel regulator is bad, and is leaking fuel into the vacuum line, the fuel regulator won't hold vacuum. A vacuum tester can be connected to the FR, if the diaphragm is leaking it won't hold vacuum. Vacuum tester is a tool which allows the user to apply vacuum to various components to check and see if they hold vacuum. They are available at harbor freight and most automotive stores.

[@BassManBobBassCovers]

Incredible and useful explanations! Thank you!

[@rogerhassell3212]

Great video. I've always viewed the operation of the FPR as a way to maintain a fixed pressure differential between the fuel rail and the intake manifold (IM). Keeping the differential pressure constant means the amount of fuel delivered through the injectors is directly proportional to the applied pulse time, the time the injectors are open. At high IM vacuum, a lower rail pressure is needed, to maintain the target pressure differential so the FPR opens up more under the high vacuum and lets more fuel return to the tank, lowering rail pressure. At open throttle, more rail pressure is needed to maintain the target pressure differential. The reduced IM vacuum causes the FPR to restrict the fuel return path, thus increasing rail pressure.

[@hunkydude322]

im beginning to obsorb some of the material on short term long term trim videos, very very interesting, and also getting a better grap at this video too, its nest to understand how the sysem works, I know it takes time to learn it, but its really neat if an indidivual likes to work on cars and not just throw parts at it, keep the good work up see ya friend

[@ricardomontez7093]

hunkydude322 a

[@ricardomontez7093]

very good presentation., I need your input

[@chui19801]

The best video regarding the subject matter. I have had an issue for a while now. Losing pressure at the regulator gauge within a minute or two. From 60 psi to 0 psi in just 2 minutes. I have a return style regulator LS swap. I might start troubleshooting based on this video. Very impressed.

[@SchrodingersBox]

Hopefully this video helps walk you through the diagnosis!

[@2326TOM]

Absolutely brilliant!

[@bibinemmanuel7375]

Very informative video, thank u

[@chrishedlund3196]

Learned so much about fuel systems from you. Didn’t want to go through all that but shops I paid + $500 didn’t diagnose. I had gnarly P0171. Thanks!

[@edwardharvey5839]

Thanks for the video! Very helpful.

[@Sandbag1300]

Excellent video. My fuel pump regulator is built into the fuel pump but now I understand the concept of the regulator and more about how to think about troubleshooting in general. I played this video at 720P and did not notice the HD. The picture was visually very well defined, not fuzzy, as in the past several videos and I find myself focused more on content of the video

[@SchrodingersBox]

Yes I always have known you were more of a content guy anyway- but I have to admit, I think the HD really, really shows on the underhood scenes, and also my hair- of course ;-) Yes the diagnosis with an internal regulator is much harder to do, you are left with pretty much pinching fuel lines but the concept is the same. My trans am is also of that design so one day I will cover diagnosis of returnless and other more "advanced" systems, but they still depend on understand basic function.

[@billyr9840]

Schrodingers Box Matt, the only thing I see that needs improvement is when you show scenes of your scan tool/lap top , hard to see, blurry !

[@SchrodingersBox]

Billy R Agreed. My new software will allow me to take screen capture instead of filming it. Should work much better. It's useless if you cant see the scantool data i agree

[@billyr9840]

You Rock Dude!

[@joshuasmith1215]

Thank you so much for this. Great learning tool.

[@etc6272]

Thank you sir for taking your valuable time in making this very important and informative video. Now I understand the function of the fuel regulator.

[@SaravanaKumar53]

love all ur vids.

[@SchrodingersBox]

Me too lol!

[@SaravanaKumar53]

lol.

[@teslarawks1673]

Good stuff in your video and very thorough saved a woman I know from buying a mass airflow sensor. Her 2003 Buick Century 3.1 is not starting when cold. It stalled on her going to work I went and looked it over It tries to start the first couple seconds and then it just turns over so my first guess was that its a fuel problem and so I pulled the tank side gas line from the filter and turn the key to the on position and it worked spraying a large amount of fuel. I put the scanner on it and it gave me a P0101 mass air flow circuit range performance problem. and a P0420 Catalyst System Efficiency below threshold (Bank 1). So I wrote those codes down and cleared the codes and it starts no problem I took it home and to her work to pick her up and to have her drop it off with me. I changed the Fuel filter and the Fuel regulator and went out this morning and didn't want to start. I cleared the codes that were not there.... and it started again. I am thinking the worst and the easiest. a ECU or the Valet system on it is activating the anti-theft. 3 minutes late calling the dealership this weekend. Going to try a different scanner and see if I can see anything of use.

[@siles870]

great videos , thanks....

[@masontymenson7955]

Great video MR MATT, personally I like the way how you explained and made it very simple and clear how to diagnose the problem with the fuel system and a void to replace unnecessary fuel system parts may not need it ,thank you very much

[@randyanderson6110]

Those looking for mistakes you make are nothing but keyboard camandos.

[@ericcagle8780]

This is a great video and now I am no longer intimidated by fuel injection after this video thank you brother!!!

[@stefanivanov8408]

thanks :)

[@danjohnson9549]

Great instructional video, Very easy to understand. I have a 92 caddy with 4.9 and it sputters and stalls at low RPM. Step on it and it takes off. I took off vac hose to FPR and it runs smooth, no evidence of fuel present, upon placing vac hose back on it speeds up and coughs, sputters etc. Fuel smell from exhaust when it does this. I have no gage but most tools and a history of problem solving. it ran good till warm.

[@SchrodingersBox]

Not sure what you are asking me for, sorry. There is no relevant data here that I can use to help with this.

[@danjohnson9549]

Sorry I do not know how to explain, thanks for the reply

[@kim7018]

Great project! You don't need to be concerned with the engineers and super mechanics who may have some issues on this! If they are so knowledgeable, they should not be here. So just talk to people like me who really belong here. As soon as i start having corrections to make, i will know i don't need the teaching. Cheers, and keep it up!

[@SchrodingersBox]

Good point. Duly noted.!

[@edwilliams2362]

Why aren't you a teacher bro! Amazing skills in delivering and conceptualizing, God bless

[@SchrodingersBox]

I do teach sometimes as part of my real job

[@gilbertojim1263]

Excellent teaching

[@edwilliams2362]

Awesome

[@darrinrivers6293]

Sir thank you so much. Im working on a 2001 Ford Expedition. Your videos have been invaluble.

[@SchrodingersBox]

Great to hear!