Fuel System - No Start/Hesitiation/Reduced Power
Bulletin No.: 05-06-04-046ADate: August 14, 2006
TECHNICAL
Subject:
Crank and No Start, Reduced Power, Intermittent Hesitation, Hesitates in High Altitude/High Ambient Temperatures (Replace with Newly Designed Fuel Pump Module Without Fuel Level Sensor)
Models:
2004-2005 Chevrolet Express Van
2004-2005 GMC Savana Van
with 4.8L, 5.3L or 6.0L Gasoline Engine (VINs V, T, U - RPOs LR4, LM7, LQ4)
Supercede:
This bulletin is being revised to update part information and add additional diagnostics. Please discard Corporate Bulletin Number 05-06-04-046 (Section 06 - Engine/Propulsion System).
Condition
Some customers may comment on a driveability condition while driving in high ambient temperatures, usually above 26.6°C (80°F) or while driving in high altitude conditions, usually above 1524 m (5000 ft) above sea level.
Diagnostic Aids
If a lack of fuel pressure is verified during the condition and no fuel pump wiring concerns are found, replace the fuel pump module. If this only occurs at the above conditions, the fuel pressure loss may be due to a fuel system vapor lock.
It is possible that the fuel system may test OK in cooler ambient temperatures or low altitude and fail under high temperatures and high altitude conditions. Refer to the following Diagnostic Information in SI:
^ Symptoms - Engine Controls.
^ Intermittent Conditions.
^ Cuts Out, Misses.
^ Fuel System Diagnosis.
Correction
Important:
When removing the fuel tank strap bolts, DO NOT use air tools. Using air tools may cause the retaining clip nut to spin preventing removal of strap bolt.
1. Remove the fuel sender assembly from the vehicle. Refer to Fuel Sender Assembly Replacement in SI.
Note:
Use extreme caution when removing the fuel level sensor from the fuel sender assembly. Failure to do so may damage the fuel sender assembly.
2. Remove the two wire fuel level sensor connector from the fuel sender assembly.
Important:
The fuel level sensor retaining tab located at the center top of the level sensor has a DUAL sided retaining tab. The fuel level sensor is retained on both the front side and the rear side of the retaining tab.
3. Using one of two pocket screwdrivers, pull the front retaining tab away from the front of the fuel level sensor while, with the second pocket screwdriver, push the fuel level sensor away and down from the fuel sender assembly.
4. Remove the fuel level sensor from the fuel sender assembly.
5. Install the old fuel level sensor by sliding the sensor up into the new fuel sender assembly (refer to Parts Information below).
6. Plug in the two wire fuel level sensor electrical connector into the fuel sender assembly.
7. Install the new fuel sender assembly with the old fuel level sensor in the fuel tank. Refer to Fuel Sender Assembly Replacement in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer