Will a Bad Fuel Pump Cause System Lean Issue?

Liz asks if a bad or failing fuel pump can cause a check engine light and system too lean issue without the car running bad. A bad fuel pump may mean too little fuel, cause a no start, or more.

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[labradormcgraw]

You always get so much information from The Humble Mechanic. Each and every question is covered in depth, with every conceivable probability covered. All presented with style, charisma and a bad-ass beard - unbeatable!

[dogodivaamorfati]

Great info thank you! People like me need this advice. I lost my dad a year ago he was my best friend and a great mechanic. I never worried about any car I ever had. Now without dad it is so difficult. It isn't easy to find a humble mechanic. I have been taken advantage of a couple of times since dad has been gone. Thank you for helping us.

[samwisegamgie]

as a tech I feel it a part of my job to inform the customer exactly what is wrong and walk them thru how I came to that diagnosis. after all it is their money.

[Lizbellzee]

Thanks Charles! I think you just assured me that going back and demanding more info is the right thing to do! I paid $135, I deserve a little more than what I got.

[danieldirzuweit]

Wow, this is an incredibly helpful answer to her question. The comprehensive technical detail and explanation of business practice are spot on. Keep up the great work!

[klwtherd]

See this is the type of expertise that makes Charles so worthwhile. He always remains professional in his opinions and isnt shy about telling you what you do when talking to a service writer or tech. Since he has been on both sides he can give you not only the best advice by also the path to follow to get the results you deserve to get as a paying customer. I feel this persons pain because more and more dealerships are not providing a detail explaination of what diagnostics they performed on your car. They just tell you what is broke but dont want to tell you how they came up with that results. All they want to be are parts changers. That is the primary reason I started seeking out information and Technicians like Charles on YouTube. Im soooo tired of having my car replaced with expensive parts to later find out that said replaced part was not REALLY the problem but this other part is. Good video

[byronarriola]

I've had the check engine light come on and when I read the code at the auto parts place they said it was the fuel cap. I replaced it with several ones from the scrap yard and that didn't work, I bought a $40 fuel cap from the dealer and that didn't work. Turns out it was the fuel pump cover at the fuel tank. The big black threaded ring that locks the lid over the fuel pump 😁 I have a 00 Passat.

[leebarros-id]

mr humble my fuel gauge on the panel goes full and then dropes to half a tank does that mean i need a fuel pump and i keep putting gas left and right so i dont run out help me if you can thanks

[redheadmetalhead]

0:55
*"Still D.R.E." starts playing*

[mentaldan]

I have nothing relevant to the video to say.
Just wanted to say we love and appreciate ya. Haha

[StanleyKubick]

I really like your calm, measured narration style. Subbed!

[dnfwme]

Hi I have 2006 230 sport and it has been very reliable car. I have all of its scheduled maintenance. Recently it started giving p2187 and p2189 codes. No other code and rough idling . On increased speeds it runs normal.

[suggesttwo]

change the fuel filter and put a strong fuel injection cleaner in the tank to clean out the entire fuel system.

[metalmauler]

no buckshot straight up good advice.good job sir.

[jonathandeville]

Lean conditions are, too much unaccounted air that the engine cannot account for since it is going passed the mass airflow sensor. a stuck injector, a faulty pressure regulator valve, a weak or clogged fuel pump, or fuel filter. Well, how does the engine know it is running lean to throw these codes you may ask? Primary and secondary 02 sensors. Primary 02 sensors are the control freaks behind the mass airflow sensors that say "Woah, too much gas, let's tame that." or "Hey bub, you have literally no gas coming out of you what's the deal?" Also, a computer may think that a misfire is cause of a lean or rich condition, and that code may be set also. For instance, I had plug #1 on my mk3 aba undone while the wife cranked, I didn't realize that the starter blew off a piece of it's housing, but when I did correct that, the engine started without cylinder 1, as I hurriedly placed the boot on the plug and it began to run fine, a simple boot unplug can set a misfire/lean condition code. As a good rule of thumb, I look at codes and look at the problem, then think around the problem too.

[vunit]

I can’t get anyone to answer this question so I figured I test my luck here, I’m having shaky engine in a 2013 sierra 2500HD with the 6.0 vortec… bought it from auction and it’s a flat bed that was used for hauling cattle…all that being said I did a basic tune up and a whole bunch of tests… new plugs, compression test, noid test (all injector plugs), spark test (all 8 cylinders) fuel pressure test that registers a little shaky between 40-60psi but then stays at 60 psi even at wide open throttle, changed transmission fluid and filter, oil & filter, air filter, cleaned MAF, and tested to see if cats were clogged by removing top upstream 02 sensors but still ran like shit maybe a bit worse, and replaced one 02 sensor that probably didn’t need replaced….I noticed it hesitates the worst between 500-1000 rpm when I barely tap the accelerator it seems to want to bog out and almost sounds like it’s going to backfire in the exhaust and in the intake, when I give it gas in park the throttle is a bit delayed and when I hold rpm’s at a certain level and hold the gas pedal steadily the rpm’s will slowly start to fall even though I haven’t moved my foot at all…I also cleaned throttle body carbon buildup but with no results… I do here an slight rattle in the exhaust downstream after the cat. I’m not getting no white/ blue/ black smoke from exhaust and no bubbles in coolant and no milky buildup or sludge under oil fill cap or dipstick… my gut feeling from the day I brought it home was fuel pump or clogged exhaust however after doing the fuel pressure test I’m not confident about spending $500 on a new pump quite yet… I scanned it a few times and deleted old codes and the ones that keep coming back are the P300 and the 02 related codes only! Bank 1 and bank 2 sensor one and 2 so I’m thinking it’s most likely not the sensors but something causing the sensors to notify the ECM. All that being said I put my ear next to the fuel pump after taking off the cap and I can hear a mechanical ticking noise that speeds up as I accelerate and after i accelerate past a certain rpm it stops making the noise… I know certain components can fail under a load however if the gauge is reading 60 psi even under load does that mean it’s not the fuel pump? Any advice is appreciated and thank you for takthe time to read all this.

[EGT]

one of the new fuel pumps in my truck is bad and it was giving me a whole mess of codes including lean and map codes

[sollykhan]

The Title for this Platform is def a Misnomer, Charles YOU'RE the Best, we get the gist of your 'character display' to be non egotistic, or overly self aggrandizing, but hey C'mon Man, give yourself a small Pat on the Back, at least for the integrity of the best knowledge that can be put out for the ignorant/ clueless Masses, Be Blessed Man, Well done, and why is there only 204 comments, and only 145K views ? should have had 4 Billion, by Now!! 🙂😇😎👍

[todaysproducts]

My 2010 370z . I have the mechanic guy change a new fuel pump. But the issue is every time I fuel got to haft tank. I only can drive 50 mile it won't go any faster unless I have to fill up the full tank

[kainhall]

had a 3.8 v6 powered 1997 Buick le saber have a bad fuel pump

you would fire it up, stick it in and it would you tried to start out in 3rd gear on a standard trans

the pump had enough pressure to run great once it got past the first 30 seconds of chug chug