Colorado 2WD L5-3.5L VIN 6 (2005)
Valve Guide Seal: All Technical Service Bulletins
Engine - MIL ON/DTC P0300/Engine Misfire
Bulletin No.: 04-06-04-081C
Date: August 18, 2005
TECHNICAL
Subject:
Check Engine Light Illuminated, Engine Misfire, DTC P0300 Set (Replace Exhaust Valve Springs and Seals)
Models:
2004-2005 Chevrolet Colorado
2004-2005 GMC Canyon
with 2.8L Inline 4 Cylinder or 3.5L Inline 5 Cylinder Engine (VINs 8, 6 - RPOs LK5, L52)
*For Engines Built Before and Including VIN Breakpoint 58261313 and Build Date 04/13/2005
*This VIN should ONLY be used in conjunction with the Dealers checking the Engine Unit Number (EUN) (label date reads T050880001 or lower) if
they think they have a truck exhibiting the issue.
Supercede:
This bulletin is being revised to update the VIN breakpoint and Engine Unit Number. Please discard Corporate Bulletin Number 04-06-04-081B
(Section 06 - Engine/Propulsion System).
Important:
The bulletin may apply to vehicles with a VIN breakpoint of 58261313 or lower. If the last 8 of the VIN is lower than 58261313, the engine unit
number (shown in SI # 889181) will have to be inspected to determine if the bulletin applies. If the engine unit number is lower than 050880001 the
bulletin applies to the vehicle. If the engine unit number is 050880001 or greater, the engine already contains the updated valve seals and springs that
are mentioned in this bulletin, so the bulletin does not apply.
Condition
Some customers may comment on a Check Engine Light On or that the Check Engine Light is flashing. An actual engine misfire may or may not be felt.
Typically this occurs during engine warm up or on deceleration after the engine is at operating temperature. Additionally, some customers may comment
on a light engine knocking noise or misfire during warm up or on a deceleration after the engine is at operating temperature. Upon investigation, the
technician will find a misfire code P0300 through P0305 and possibly a P0420.
Important:
If a DTC P0420 is stored along with DTC(s) P0300 through P0305, the catalytic converter diagnostics in Service Information (SI) must be followed
to determine if the catalytic converters are operating properly.
Correction
Perform the diagnosis for the P0300 DTC as found in the appropriate section of Service Information (SI). If no concerns are isolated through the
diagnosis, then replace all of the exhaust valve springs and seals. It will be necessary to remove the intake and exhaust camshafts. Refer to and
copy all of the appropriate section(s) of Service Information (SI) repair procedures referenced below before attempting this repair. Refer to the
parts information below to determine what bolts, valve springs, seals and gaskets will be necessary during reassembly.
3.5L Inline 5 Cylinder Engine (VIN 6 - RPO L52)
^
SI Document ID # 1220699 - Camshaft Replacement
^
SI Document ID # 1220636 - Valve Rocker Arm and Valve Lash Adjuster Replacement
^
SI Document ID # 1220642-Valve Stem Oil Seal and Valve Spring Replacement SI Document ID # 1220634 - Camshaft Cover Replacement
^
SI Document ID # 1219989 - Camshaft Position (CMP) Sensor Replacement Exhaust
^
SI Document ID # 1219991 - Camshaft Position (CMP) Sensor Replacement Intake
^
SI Document ID # 1220628 - Intake Manifold Replacement
