Code P0171 help

[whozleft]

Hi all,

Can anyone help me with this code my 1997 LeSabre keeps coming up with. Sometimes I can cancel the code with my code rader and it will stay off for a couple days. Then the next time it may come on the next day. Always the same code. I have been told to run injector cleaner through it, but so far this hasn't helped. Should I get the throttle body cleaned? Is this a possible culprit? Guess I'm not sure what to do. The care seems to run fine except for a miss at speed sometimes.

Any sugestions will be greatly appreciated.

Thank you,
Gary

[MT-2500]

Originally Posted by whozleft

Hi all,

Can anyone help me with this code my 1997 LeSabre keeps coming up with. Sometimes I can cancel the code with my code rader and it will stay off for a couple days. Then the next time it may come on the next day. Always the same code. I have been told to run injector cleaner through it, but so far this hasn't helped. Should I get the throttle body cleaned? Is this a possible culprit? Guess I'm not sure what to do. The care seems to run fine except for a miss at speed sometimes.

Any sugestions will be greatly appreciated.

Thank you,
Gary

How many miles on tune up?
Any other codes?
Check fuel pressure and maf sensor and plugs fuel filter to start with.
Pull vacuum hose off of fuel pressure regulator and check for gas in it.

[BNaylor]

Welcome to AF.

DTC P0171 is Fuel Trim System Lean. The PCM module will read the 02 sensor signal voltage and then adjusts fuel delivery based on the voltage. It looks at Long Term (LT) and Short Term (ST) fuel trim values. Ideal fuel trim is zero. Fuel trim greater than zero indicates the PCM is adding fuel to compensate for a lean condition. Fuel trim less than zero indicates the PCM is reducing the amount of fuel to compensate for a rich condition. If abnormal DTC P0171 sets. PCM is normally is the closed loop mode.

Cleaning the throttle body is part of the corrective action and checking for any obstructions in the intake system like a clogged air filter or throttle body inlet screen. Also, clean the IAC valve.

Other items that can cause the DTC are 02 sensor, MAF sensor, EGR valve, throttle position sensor (TPS), vacuum leak, insufficient fuel pressure or leaking fuel injector o-ring seals.

[whozleft]

I did a tune up on this car about 1500 miles ago. Have replaced the EGR and aur filter along with all new AC plugs. Will have the throttle body cleaned next and see if that helps. I also have determined to go ahead and change the fuel filter since I don't know if it's ever been done. The care has abour 87,000 miles on the odometer. I bought it from the original owner. thanks you all for your help and suggestions so far. i will continue to follow the thread and report back what I find.