3800 DTC P0171, Fuel Trim System Lean Bank 1???

[Bliss Racing]

WHat the hell does that mean, how bad is it????

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[1quick]

When I had a lean bank one it was a vaccume leek on the front side of the supercharger bace gasket could be your lower intake manifold gasket but It means you have a vaccume leek on the front sid of your motor.


Brett

 

[Bliss Racing]

Originally posted by 1quick98_gs@Mar 28 2005, 08:42 AM
When I had a lean bank one it was a vaccume leek on the front side of the supercharger bace gasket could be your lower intake manifold gasket but It means you have a vaccume leek on the front sid of your motor.


Brett

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Would that be causing a misfire?? I am throwing code 0300 as well--Random Misfire.

 

[imported_GraFFix]

I would check the front O2 sensor before anything else...unless you've been into the motor then its possible for a leak other then that I hightly doubt its a vaccume leak. most likely its your O2...

If you want to check for a leak just start the car and spray some carb cleaner around the intake manifold and the supercharger...see if you get any jumps in idle

Other things to check into are your fuel injectors, MAF, fuel filter, fuel pressure regulator. but personally I would start with the easy thing and check the O2...make sure you get a AcDelco one all the others seem to have issues with our cars. at least from my experiance. I know caspers has the O2's for our cars a little cheaper then any store you might want to check with them for that. Plus their in the NW burbs depending where you are you can always go pick it up. www.casperselectronics.com talk to Justin

HTH

 

[zeez gtp]

check for a vac leak on the s/c. i threw a code just like it, and my s/c gasket was leaking in the back of the s/c. my o2's were non existent when i had that vac leak.

 

[fastcash]

big issue is also when you remove the throttle body screen, if you did, replace it and it will go away.

 

[Bliss Racing]

OK......all vac leaks fixed.....Brand new Fuel injectors....and threw that code again P0171....system too lean Bank 1...

What the FUCK?!?!? I am about to sell this car....i am tired of this shit.

 

[jk99gtp]

Originally posted by Bliss Racing@Apr 8 2005, 05:37 PM
OK......all vac leaks fixed.....Brand new Fuel injectors....and threw that code again P0171....system too lean Bank 1...

What the FUCK?!?!?  I am about to sell this car....i am tired of this shit.

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Have you checked fuel pressure? A bad fuel pressure regulator/fuel filter/fuel pump can cause lean issues. I believe at idle you should be at 44psi, someone please correct me if I'm wrong on this one..

Thanks.

 

[Bliss Racing]

The saga continues.....so my boost bypass control unit was bad, so i got a new one on the car. Code went away for about a week....yesterday comes back one, same code!!

I do have an exhaust leak at the cross over...would that cause the lean out code?? Could the 02 be bad??

What the hell is going on?!?!?

 

[horist]

Originally posted by Bliss Racing@Apr 14 2005, 12:16 PM
The saga continues.....so my boost bypass control unit was bad, so i got a new one on the car.  Code went away for about a week....yesterday comes back one, same code!!

I do have an exhaust leak at the cross over...would that cause the lean out code??  Could the 02 be bad??

What the hell is going on?!?!?

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An exhaust leak upstream of the O2 sensor can cause false lean readings... fresh air will be sucked into the exhaust stream, so the O2 sensor will see unused oxygen and as a result add more fuel... eventually it maxes the long term fuel trims out and can't add anymore fuel but it's still reading lean ...

bad O2 can also cause it... but if you have an exhaust leak upstream (before the cats) then that's probably the culprit ... plus if it was a bad O2 it'd probably set an insufficient switching code, not a lean code...

Only other option is a vacuum leak past hte MAF, but looks like that's been covered already ... I suppose a clogged injector could cause this too ... but i'd bet that exhaust leak is the main prob

 

[imported_GraFFix]

Last time i had a P0171 it was my O2...thats why i said to check your O2 a couple weeks ago in my last post.

Id definatly check it out or find someone close to you with and swap thier good one with your and see if the code goes away...then youll know for sure before you go and buy one.

 

[EmersonHart13]

Getting to the fuel pressure, how hard is the regulator to change, and is the only way to check it with one of those handy dandy plug in gauges?

Thanks,

John

 

[imported_GraFFix]

Its not that bad to replace but you need snap ring pliers to get the retaining ring out and also to put it back in. you can try to get it off/on without them but it will be a PITA. basically pull the ring off then pull the regulator out then put the new one back in and replace ring..its pretty simple.

About checking pressure on it i dont know of any other way to do other then with a gauge.