WenmarOpen by Wenmar Pro

Service bulletin 866504

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id609635
Published by NHTSA2000-04-05
Manufacturer's number866504
Manufacturer's date1998-08-01
NHTSA componentENGINE AND ENGINE COOLING:ENGINE:GASOLINE

NHTSA's summary

ENGINE EXHIBITS A HIGH IDLE OR FLARE WHEN SHIFTING GEARS OR DISENGAGING THE CLUTCH SUCH AS WHEN SLOWING DOWN OR STOPPING.

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Engine

Vehicles listed
CHEVROLET S SERIES1996 to 1997
CHEVROLET T SERIES1996
CHEVROLET T SERIES1997
GMC S SERIES1996 to 1997
GMC T SERIES1996
GMC T SERIES1997

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
0206040602003-03-28. Service bulletin. AUTOMATIC ENGINE SHUTDOWN FEATURE. *TT
0206030022002-06-10. Service bulletin. CUSTOMERS MAY COMPLAIN THAT THE ENGINE WILL NOT START. *JG
0206030022002-05-21. Service bulletin. CUSTOMERS MAY COMPLAIN THAT THE ENGINE WILL NOT START. *SLC
0206040062002-04-02. Service bulletin. SOME CUSTOMERS MAY COMMENT ON SERVICE ENGINE SOON LAMP ON, MALFUNCTION INDICATOR LAMP ILLUMINATIONS INTERMITTENTLY, DIAGNOSTIC TROUBLE CODE SET, BLOWN FUSES, AND ENGINE WILL NOT START. *TT
000601023A2002-03-25. Service bulletin. INFORMATION USED WHEN DIAGNOSING NOISE CONDITIONS SUCH AS ENGINE RATTLE NOISE, SPARK KNOCK AT 2000 - 2500 RPM RANGE, UNDER A MODERATE TO HEAVY LOAD WITH A WARMED UP ENGINE. *TT
99066D2002-03-25. Service bulletin. SOME OWNERS MAY EXPERIENCE A SERVICE ENGINE SOON LIGHT, MISFIRE, ROUGH IDLE ORHARD START DUE TO A DEPOSIT BUILD-UP ON THE SEQUENTIAL CENTRAL PORT FUEL INUJECTOR (SCPI) POPPET VALVE(S). *TT
000604003A2002-03-22. Service bulletin. SOME CUSTOMERS MAY COMMENT ON ROUGH IDLE AFTER START UP, ESPECIALLY AFTER SETTING OVERNIGHT. *TT
0006040142000-10-11. Service bulletin. SOME CUSTOMERS MAY COMMENT ON HARD, NO, OR SLOW START, BACKFIRE OR KICKBACK DURING CRANK / START, GRINDING OR UNUSUAL NOISES DURING CRANK, DIAGNOSTIC TROUBLE CODE P0338. *TT
99066B2000-07-25. Service bulletin. SOME OWNERS MAY EXPERIENCE A SERVICE ENGINE SOON LIGHT, MISFIRE, ROUGH IDLE OR HARD START. **MR
990782000-04-06. Service bulletin. CERTAIN VEHICLES EQUIPPED WITH DIESEL ENGINES MAY EXHIBIT ENGINE AIR INDUCTION CONTAMINATION. *TT