mightymouse

P2178-FUEL TRIM UNDER ACCEL-RICH
P0299-TURBO UNDERBOOST.

sounds like these two can be corrected with a factory reflash??? imo,the fuel trim thingy is causing the underboost. anyone had these codes before???

anyhow he's at the dealer(my car lol)being serviced. they will also take care of a screw that got into my right front tire. they gave me an enterprise rental till mine is done...grandprix that's been smoked in...blah!!!

Jookster126

I DONT KNOW IF THIS WILL HELP, BUT THERE IS A REPROGRAM OUT FOR THE 2008 HHR SS. HERE IS THE BULLETIN FROM GM







#08-06-04-034: LNF Malfunction Indicator Lamp (MIL), Check Engine Light Illuminated with One or More of the Following DIagnostic Trouble Codes (DTCs) P0096, P0335, P0806, P2199, P2261 (Reprogram ECM) - (Jun 12, 2008)


Subject: LNF Malfunction Indicator Lamp (MIL), Check Engine Light Illuminated with One or More of the Following Diagnostic Trouble Codes (DTCs) P0096, P0335, P0806, P2199, P2261 (Reprogram ECM)


Models: 2008 Chevrolet HHR SS

with ECOTEC® 2.0L I-4 Cylinder Turbocharged Engine (VIN X -- RPO LNF)




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

Condition
Some customers may comment on Malfunction Indicator Lamp (MIL), Check Engine Light Illumination. Typically, there will be no driveability symptoms or engine performance concerns.

Upon further investigation, one or more of the following DTCs may be stored in the ECM:

• DTC P0096: Intake Air Temperature (IAT) Sensor 2 Performance

• DTC P0335: Crankshaft Position (CKP) Sensor Circuit

• DTC P0806: Clutch Pedal Position (CPP) Sensor Circuit Performance

• DTC P2199: Intake Air Temperature (IAT) Sensor 1-2 Correlation

• DTC P2261: Turbocharger Bypass Valve Stuck Closed

Correction
If routine diagnosis using SI does not reveal any obvious cause, Do Not replace the following components :

• Intake Air Temperature (IAT) Sensor for DTC P0096 or P2199

• Crankshaft Sensor for DTC P0335

• Clutch Pedal Position (CPP) Sensor for P0806

• Turbocharger Bypass Valve for DTC P2261

Important: Verify that the 12-volt battery has a battery charge of 12 to 16 volts. The battery must be able to maintain a charge during programming. Only use approved Midtronics 165-PCS charger or equivalent to maintain proper battery voltage during programming.

Important: Select J2534 MDI and Reprogram ECU from the Select Diagnostic Tool and Programming Process screen. The J2534 MDI will reprogram the modules in less time than the Tech 2® scan tool.

Reprogram the ECM using the latest calibration if the above concern is encountered. A revised engine calibration has been developed to address these issues. Reprogram the ECM with the latest software calibration. The service calibration is available on TIS2WEB using the Service Programming System (SPS). As always, make sure your Tech 2® is updated with the latest software version.

Warranty Information
For vehicles repaired under warranty, use:

Labor Operation
Description
Labor Time

J6354
Powertrain Control Module -- Engine Reprogramming with SPS
Use Published Labor Operation Time

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

Nebulous1

Sounds like there might be an air pressure leak in the turbo system.

Several owners have reported air pressure leaks from loose parts that clear up after tightening things. That would account for the underboost, and underboost would account for rich trim (since it would not be receiving as much air as expected).

astropods

I'm with Nebulous on the boost leak in the system. Your losing boost so the motor throws the codes for rich, because the motor is expecting the extra air from the turbo boost that isn't there so there's too much fuel, and turbo underboost because well, there's a leak. Take it back to the dealer and have them check for loose clamps, hoses and what not. I'll bet all the money in my wallet that's the problem

P.S. reflash won't fix those problems but you already know that....

mightymouse

you know something??? i think you're right. before i took it in yesterday,my charge pipe from the turbo that runs to the driver side was loose at the bottom. i told them to tighten it . well it was tight when i got it back,but now it's loose again and the problem is back. already made the call to them to get info on what he did down there.