Fuel System - SES Lamp ON/DTC P0638: Overview

Subject:
Service Engine Soon (SES) and/or Reduced Power Lamp Illuminated, Limited Throttle Response Following Cold Engine Start Up DTC P0638 (Relocate Small Primary Positive Crankcase Ventilation Hose)
# 04-06-04-074 - (10/11/2004)

Models:
2002-2003 Saturn VUE Vehicles with 3.0L V-6 Engine (VIN B - RPO L81)

Attention:
Fixed Operations Manager and Technician

Condition

Some customers may comment on the Service Engine Soon (SES) and/or Reduced Power lamp illuminating and limited throttle response immediately following cold engine start up during subfreezing temperatures. Diagnostic trouble code (DTC) P0638 may be stored in the engine control module (ECM).

Cause

This condition may be caused by crankcase vapors inside the throttle body collecting at the throttle plate base as engine cools down while shut off resulting in restricted throttle plate movement immediately following cold engine start up during subfreezing temperatures.

Correction

Re-locate primary positive crankcase ventilation (PCV) hose from throttle body to intake manifold top cover and re-route secondary PCV hose over intake manifold. Refer to service procedure in this bulletin. If the vehicle has had PCV hose routing updated per Corporate Bulletin Number 04-06-01-001 (look for labor code J6020 in vehicle history), it is not necessary to repeat steps 29-31.





Parts Information

Claim Information

To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System for J6020 (Hose, Crankcase Ventilation - Replace). An Add Time has been included for re-routing the PCV hose to the Intake Manifold. This Add Time can only be used once per vehicle.





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