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Service bulletins for the 2004 GMC Envoy

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

744 on file from NHTSA, as of 2026-10-19.

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Only bulletins with component: Exhaust and emissions are shown. Show all

Bulletins, newest first
16NA3832019-07-01. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. This informational bulletin advises of a new fuel injection kit used for decarbonizing the intake valves, and explains how toptier fuels should be used to reduce carbon build up.
PIP4925B2019-03-18. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This preliminary information document communicates a tip on the way to diagnose possible induction or exhaust air leaks using the evaporative emission cart smoke machine and ultrasonic leak detector tools.
PIP4581B2018-06-04. Service bulletin. ENGINE; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV); EQUIPMENT. This Preliminary Information communication provides information to the technician about vehicles that may have an engine rattle that star after the engine was repaired ant the repair required the crankshaft balancer removal and replacement. When the rattle noise is duplicated without the Service Engine Soon Malfunction Indicator Lamp and Service Information diagnosis does not isolate the cause the crankshaft balancer bolt should be re-torqued per the specifications states in Service Information. When the rattle noise is duplicated with the Service Engine Soon Malfunction Indicator Lamp and Diagnostic Trouble Code P0016 or P0017 and Service Information diagnosis does not isolate the cause the crankshaft balancer bolt should be re-torqued per the specifications states in Service Information. If tightening the bolt repairs the rattle noise but the Diagnostic Trouble Code P0016 or P0017 continue to set technician should follow published Service Information diagnostics for the Diagnostic Trouble Code. If Service Information diagnostics for the Diagnostic Trouble Code do not lead to a repair for the Diagnostic Trouble Code remove the crankshaft timing sprocket and inspect the crankshaft alignment pin and the related groove of the sprocket for obvious wear. If wear is present replace the sprocket and pin and retest.
060601010D2018-06-04. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR. This informational bulletin explains how the catalytic converters may need an inspection, cleaning or replacement if debris have entered the exhaust system.
PIP5232A2018-05-07. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR. This Preliminary Information communication provides information to the technician about gasoline powered cars, mid-size trucks, light duty trucks, and heavy duty trucks with premature catalytic converter failures. It is recommended to inspect for a poor crimp on the grounds ring terminal at the engine block for the bank with the concern and repair the wire.
PIP52322018-05-07. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR. This Preliminary Information communication provides information to the technician about gasoline powered cars, mid-size trucks, light duty trucks, and heavy duty trucks with premature catalytic converter failures. It is recommended to inspect for a poor crimp on the grounds ring terminal at the engine block for the bank with the concern and repair the wire.
PIP5232B2017-08-15. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR. This Preliminary Information communication provides information to the technician about gasoline powered cars, mid-size trucks, light duty trucks, and heavy duty trucks with premature catalytic converter failures. It is recommended to inspect for a poor crimp on the grounds ring terminal at the engine block for the bank with the concern and repair the wire.
PIT4943D2017-08-15. Service bulletin. FUEL SYSTEM, GASOLINE; FUEL SYSTEM, OTHER:STORAGE:TANK ASSEMBLY; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This Preliminary Information communication provides information to the technician about vehicles that have a Service Engine Soon Malfunction Indicator Lamp. Technician may find Diagnostic Trouble Code P0442. Technician will need to review Techlink article from May 2013 titled "Using the Evaporative Emissions System Tester" Technician will need to follow these steps to help diagnose the issue. First after the P0442 has been verified do not disturb any of the fuel system components. The technician now can use the scan tool to close the Evaporative Emissions System. If possible change the tank pressure sensor units from inch_H2O to milimeter_Hg for better resolution. Now the vehicle can be stared to monitor the tank pressure sensor output value for approximately two minutes. If the tank pressure sensor value does change, pressurize the fuel tank side of the purge solenoid with the GE 41413-A / J 41413-A and the necessary adaptors. Now add smoke and allow pressure to stabilize for 2 minutes. If smoke is allowed to pass through the purge solenoid, replace the purge solenoid. If the tank pressure sensor value does not change, then install CH-48096 adaptor between the purge line from the canister and the purge solenoid. With the Evaporative Emissions System closed, pressurize the system through the CH-48096 adaptor and allow the system to completely stabilize, by observing the Press / Vac Gauge for a minimum of 5 minutes. Now add smoke to the system with GE 41413-A / J 41413-A after system stabilization. Now inspect the purge solenoid, engine side, fuel cap, canister vent solenoid filter and any line quick connects. When the leak is unable to be located, test under a vacuum condition. his type of leak may be detected by using the scan tool Purge/Seal function to create a vacuum in the Evaporative Emissions System and then observe the FTP sensor parameter for vacuum decay.
PIP5232C2017-08-15. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR. This Preliminary Information communication provides information to the technician about gasoline powered cars, mid-size trucks, light duty trucks, and heavy duty trucks with premature catalytic converter failures. It is recommended to inspect for a poor crimp on the coil grounds ring terminal at the engine block for the bank with the concern and repair the wire.
PIP-4492P2011-03-16. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV). BUICK/CADILLAC/CHEVROLET/GMC/HUMMER/PONTIAC/SAAB: OIL CONSUMPTION AND/OR EXHAUST SMOKE-POSSIBLE PCV BAFFLE OR LIFTER CONCERN. UPON INSPECTION, OBVIOUS OIL WILL BE FOUND IN THE INTAKE MANIFOLD AND/OR PCV VACUUM TUBE. *PE UPDATED 3/21/11. *PE UPDATED 5/9/11. *PE UPDATED 5/25/11. *PE UPDATED 06/16/2011. *KB UPDATED A SECOND TIME ON 06/16/2011. *KB UPDATED 6/27/11. *PE
5102005-09-02. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. 2004 SECONDARY AIR INJECTION SYSTEM- IN 6 CYLINDER ENGINE INCORPORATES A NEW AIR PUMP AND AN ELECTRONIC AIR SHUT OFF VALVE. *SC
0506040212005-05-14. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. REVISED INSPECTION/MAINTENANCE (I/M) EVAPORATIVE EMISSION (EVAP) SYSTEM SET PROCEDURE. *TT
0506040142005-05-13. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. DIAGNOSTIC AIDS FOR DIAGNOSTIC TROUBLE CODES P0440, P0455 AND/OR P0442 - EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK. *TT
32092005-02-01. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. EXHAUST MOAN AT IDLE OR PARKING LOT MANEUVERS. *EH

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.