D4u2s0t

I know this has been talked to death, but i searched for a long time for an answer and didn't find one. is there anyway to fix this on the 2.2? I know on the 2.4 and 2.0 you can adjust the fuel with hptuners, but since there's nothing out for the 2.2 is there anyway to fix this? or should i just not go wot until it can be tuned. thanks guys

Witt

Tighten all your intake piping connections. If you are using the stock piping in which the MAF sensor sits in its either leaking somewhere or you have a problem with air turbulance hitting your MAF.

YellowLT

Diablo Sport will have their tuning released soon.

Halfcent

Its the fuel trim system lean code, and no, I know of no way to "fix" it other then to clear it with a scanner. It's just such a very touchy trigger on this ECM program. I set it off with my stock airbox. I keep a Matco pocket scanner in the car and clear it.

Witt

A maf translator would be an easy yet slightly expensive way to fix it. What actually is happening is your MAF calibration is off. For X amount of airflow your PCM is programmed to add Y amount of fuel. Oxygen sensor data is used to correct these numbers (a la trims). What happens with a P0171 code is the PCM determined that for X amount of airflow it takes Y+20% or more fuel to achieve a stoich burn at idle and part throttle.

As far as going WOT, that can't be determined unless you have a UEGO (wideband) installed to see whats actually happening when the PCM drops out of closed loop and adds extra fuel, richer than a stoich burn. Most of the time you will go slightly leaner than the PCM originally commands since your entire MAF calibration is probably off by at least 20% but again, it can only be determined by using a UEGO gauge at wide open throttle.

D4u2s0t

thanks, that's what I did this morning. I figure that was all I could really do. I recently put on a custom intake, which keeps the stock airbox since I have the SAI. One of the clamps around the throttle body was broken, so it was a little loose, i'm wondering if that's what caused it. I also gave everything a good tighten. Hopefully that will be enough.

but where the MAF sits is stock.

yea, i cleared the code too.

carbombss

Subject: 2.0L/2.2L LSJ/L61 Engine Malfunction Indicator Lamp (MIL)/Service Engine Soon (SES) Lamp Illuminated with DTC P0171, Fuel Trim System Lean, Set (Reprogram ECM) #06-06-04-033 - (06/21/2006)



Models: 2005-2006 Chevrolet Cobalt, Cobalt SS Supercharged

2006 Chevrolet HHR

2004-2006 Chevrolet Malibu

2005-2006 Pontiac Pursuit (Canada Only)

2004-2005 Saturn ION Redline

2005-2006 Saturn ION

with Ecotec™ 2.0L or 2.2L I-4 Engine (VINs P, F - RPOs LSJ, L61)




--------------------------------------------------------------------------------

Condition
Some customer may comment that the MIL/SES lamp is Illuminated. Further diagnostic investigation with a scan tool may reveal a DTC P0171 Fuel Trim System Lean. No other driveability or performance concerns may be reported.

Cause
The most likely cause of this issue may be that the engine calibrations need to be updated to correct a variation in the Mass Air Flow Sensor.

Correction
DO NOT replace the MAF sensor, the ECM or any other parts.

Important:

• Chevrolet/Pontiac Dealers: The ECM calibration is available to dealerships as part of TIS2000 incremental satellite update version 6.5, which was broadcast to dealers June 12, 2006 or later. For the dealerships that use CDs, they were mailed out June 2006 or later.

• Saturn Retailers: Before installing the new ECM calibration, make sure the Saturn Service Stall (SSS) version is TIS 6.5 2006 or later.

• While the ignition is OFF, apply the parking brake to disable the daytime running lights (DRLs) prior to starting reprogramming procedures

• The technician must select the "Reprogram" option in order to reprogram the ECM.


Reprogram the ECM with the latest calibration. This calibration, or any that follow, is designed to address this DTC P0171 concern. Refer to Service Programming System (SPS) in SI for reprogramming procedures. As always, make sure your Tech 2Ž is updated with the latest software version

Witt

^^Good info. The above reflash is more than likely because the stock calibration is quite poor and very close to already tripping a trim code.

Halfcent

Hey, look at that. I didn't know they had a software update for it.

XM15

I wouldn't worry about going WOT. It would be an issue if we were f/i, but I think we (I have the lean code as well) will be fine until tuning comes out.

Zerospeed

okay this is the definitive awnser to the p0171 problem, my 07ls has had that code stored in it since october of 06. I keep looking at all data and I keep finding Tech Service Bulletins on a computer update for 05-06 chevys! Take it in to the dealer, they will sattallite update your car for free. If you have aftermarket anything don't worry they dont even lift the hood.