MIL Service Engine Soon Telltale On and/or Reduced Power Telltale On with DTCs P1510 and/or P1516 Set Duringand Engine Start at Ambient Temperatures Less Than -7 Degrees Celsius

Some customers may comment about the SERVICE ENGINE SOON telltale and/or the REDUCED POWER telltale coming on. When this condition occurs, DTC(s) P1510 and/or P1516 may also be set and stored by the ECM.

This condition may be caused by condensation freezing at the base of the throttle plate after the vehicle has been driven and then parked low ambient temperatures. When the engine is first started, the ice build up on the base of the throttle plate may cause it to momentarily stick in the closed position. If this occurs, DTC P1510 and/or P1516 may be set and the ECM will command the REDUCED POWER telltale On while limiting engine rpm and power.

Refer to the Engine/Emission Controls section of the 2000 L-Series L81 Engine Service Manual and follow the diagnostic aids for DTC P1510 and/or P1516. After DTC P1510/P1516 diagnostic aids have been followed and any repairs have been completed, determine whether the new ECM service calibration is required according to the procedure in this bulletin.

1. Connect a Tech 2 to the vehicle.
2. Navigate to the 3.0 liter POWERTRAIN menu.
3. Select ID INFORMATION.
4. Select ENGINE INFORMATION.
5. Read ECM CALIBRATION.

•	If ECM calibration is 02610601, 02610602, or 02620101, reprogram ECM with the Revised Service Calibration detailed in the table below. (Refer to "Service Programming System [SPS]" in the Saturn Service Stall System [SSS] User Guide" for reprogramming procedures.)

•	If ECM calibration is not 02610601, 02610602, 02620101, do not reprogram the ECM because the ECM already has a calibration installed to address this condition. Refer to additional diagnostic information in the 2000 L-Series L81 Engine Service Manual.