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Engine - MIL ON/Runs Rough/Stalls

BULLETIN NO.: 94-T-13

ISSUE DATE: April, 1994

GROUP/SEQ. NO.: Engine-04


CORPORATION NO.: 486103

SUBJECT:
Malfunction Indicator Lamp (SERVICE ENGINE SOON Telltale Lamp) On, Engine Runs Rough and/or Stalls at Idle, Diagnostic Trouble Codes 45 and/or 49 May Set-SOHC (LKO) Engines (Replace TBI Tube Module)

MODELS AFFECTED:
1991-1994 Saturns with SOHC (LKO) engines, equipped with plastic TBI tube module assembly.

CONDITION:
The malfunction indicator lamp (MIL) (SERVICE ENGINE SOON telltale lamp) may be On, engine may run rough and/or engine may stall at idle. PCM diagnostic trouble codes 45 and/or 49 may also be present.

CAUSE:
The gasket on the plastic TBI tube module on the TBI assembly and/or the connectors of the vacuum harnesses from the vacuum tube module to the MAP sensor, EGR solenoid/valve and the EVAP canister purge solenoid may be damaged, producing a vacuum leak.

CORRECTION:
Inspect the gasket of the plastic TBI tube module and vacuum harness connectors according to the procedure in this bulletin.





PROCEDURE:

1. Remove vacuum source harness assemblies, connecting the TBI tube module to the EVAP canister purge and EGR solenoids, EGR valve and MAP sensor, from the TBI tube module.
2. Remove the vacuum source harness assembly from the MAP sensor and the vacuum source harness assembly from the EGR valve and EVAP canister purge solenoid.
3. Inspect the vacuum source harness assemblies for any deterioration or splitting. If either of the vacuum source harness assemblies show signs of deterioration or splitting, replace with a new vacuum source harness assembly, using the appropriate part number given under "PARTS REQUIREMENTS" in this bulletin.
4. If the vacuum source harness assemblies do not show signs of deterioration or splitting, remove the two bolts securing the TBI tube module to the throttle body assembly.
5. Remove the TBI tube module and inspect the gasket for deterioration and/or splitting.
6. If the gasket shows signs of deterioration or splitting, replace the TBI tube module kit with a new metal TBI tube module kit (P/N 21007009).

IMPORTANT:
The new metal TBI tube module kit requires a paper gasket, which is included with the TBI tube module kit (P/N 21OO70O9).

7. If the gasket of the plastic TBI tube module does not show signs of deterioration or splitting, refer to diagnostic trouble code charts in the "Electronic Engine Controls Service Manual" for the diagnostic trouble code(s) set. If no diagnostic trouble code is set, refer to the "Cause-Complaint-Condition" charts in the "Engine Mechanical Service Manual."

PARTS REQUIREMENTS:
21007009 TBI Tube Module Kit (Metal)
21006243 Harness Asm-Vac Sce (MAP)
21000843 Harness Asm-Vac Sce (EGR/EVAP)

CLAIM INFORMATION:





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