(MIL) Service Engine Soon Telltale Illuminated With DTCs P0171 and/or P0174

Subject: (MIL) SERVICE ENGINE SOON Telltale Illuminated With DTCs P0171 and/or P0174 (Retorque Intake Manifold Vacuum Chamber Bolts, Install Vacuum Chamber Springs)

Models: 2002-2003 Saturn VUE -- Built Up To and Including VIN Breakpoint 3S854417 with 3.0L, V6 Engine (VIN B -- RPO L81)

Condition

Some customers may comment on the (MIL) SERVICE ENGINE SOON telltale being illuminated. (DTC(s) P0171 - Fuel Trim System Lean Bank 1 and/or DTC P0174 - Fuel Trim System Lean Bank 2 may be set and stored in the ECM memory.)

Cause

This condition may be caused by insufficient torque on the intake manifold vacuum chamber bolts. Under deceleration, enough vacuum can be created inside the intake manifold to lift the vacuum chamber off it's seal creating an intermittent vacuum leak.

Correction

Refer to the service procedure in this bulletin to retorque the intake manifold vacuum chamber bolts and install the vacuum chamber springs.

Procedure:

Notice: When servicing intake manifold, do not use power tools. Damage to threads or manifold may occur.

1. Loosen clamp at air cleaner assembly and throttle body assembly.

2. Remove attachment bolts from outlet resonator/duct assembly. Download File PDF