EXPERTEC TSB (95-T-34)

EXPERTEC TSB

TECHNICAL SERVICE BULLETIN

MIL (SERVICE ENGINE SOON) TELLTALE ON INTERMITTENTLY

95-T-34

06/21/1995

SUBJECT

MIL (SERVICE ENGINE SOON) Telltale On Intermittently at Idle after a Cold Start at High Altitudes with DTC 24 in PCM Memory - Manual Transaxle Vehicles Only (Install New PCM Calibration)

MODELS AFFECTED

1995 Saturns built before and including the following VINS:

SZ361431 - SOHC (L24)

SZ361738 - DOHC (LLO)

CONDITION

Some customers may comment about the MIL (SERVICE ENGINE SOON) telltale being On intermittently during idle after a cold start when operating vehicle in high altitudes. Also, a diagnostic trouble code (DTC) 24 is stored in the powertrain control module (PCM) memory.

IMPORTANT: The MIL (SERVICE ENGINE SOON) telltale will go Off when vehicle reaches a speed greater than 5 km/h (3 mph).

CAUSE

Intake manifold pressure parameter at altitude exceeds limit currently set in the PCM/EC diagnostic test for DTC 24.

CORRECTION

Follow the diagnostic procedures for DTC 24 in the "1995 Electronic Engine Controls Service Manual" and repair as required. After repairs have been performed, clear PCM DTCs and install new PCM/EC calibration in following table. (Refer to "Reprogramming EEPROM" in the "Service Stall System User Guide.")

If no trouble is found while performing diagnostic procedures, clear PCM DTCs and install new PCM/EC calibration according to the following calibration chart. (Refer to "Reprogramming EEPROM" in the "Service Stall System User Guide.")

1995 CALIBRATIONS DOHC (LL0) and SOHC Engine equipped with Manual Transaxles

CLAIM INFORMATION

To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System as follows: