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Service bulletin 866503

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 id615078
Published by NHTSA2000-12-27
Manufacturer's number866503
Manufacturer's date1998-07-01
NHTSA componentENGINE AND ENGINE COOLING:EXHAUST SYSTEM

NHTSA's summary

SOME VEHICLES MAY SET A FALSE OBD II WITH DIAGNOSTIC TROUBLE CODE P1404. *TT

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, Exhaust and emissions

Trouble codes named

P1404

Vehicles listed
CHEVROLET C SERIES1998 to 1999
CHEVROLET G SERIES1998 to 1999
CHEVROLET K SERIES1998 to 1999
CHEVROLET L SERIES1998 to 1999
CHEVROLET M SERIES1998 to 1999
CHEVROLET P SERIES1998 to 1999
CHEVROLET S SERIES1998 to 1999
CHEVROLET T SERIES1998, 1999
FORD L SERIES1999
GMC C SERIES1998 to 1999
GMC G SERIES1998 to 1999
GMC K SERIES1998 to 1999
GMC L SERIES1998
GMC M SERIES1998 to 1999
GMC P SERIES1998 to 1999
GMC S SERIES1998 to 1999
GMC T SERIES1998, 1999
OLDSMOBILE BRAVADA1998

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
1300890092023-12-11. Service bulletin. Expanded Availability for Remanufacture and Return (R&R) Electronic Control Modules
0406030022005-03-11. Service bulletin. DIAGNOSTIC INFORMATION FOR INTERMITTENT VEHICLE NO CRANK DEAD BATTERY. *EH
020682004-07-10. Service bulletin. NO START WITH DIAGNOSTIC TROUBLE CODE (DTC) P1626 OR P1631. ALSO INCLUDES 1998-2004 CHEVROLET, GMC FULL SIZE TRUCKS/ UTILITIES/ VANS. *TT
012252004-07-08. Service bulletin. ENGINE COOLANT LEAK AT INTAKE GASKET. * MJ
0306010242003-12-04. Service bulletin. RATTLE NOISE IN ENGINE. *TT
030601024A2003-12-02. Service bulletin. RATTLE NOISE IN ENGINE. *TT
000604003B2003-04-28. Service bulletin. ROUGH IDLE AFTER START, AND/OR A SERVICE ENGINE SOON (SES) LIGHT. VARIOUS MODELS INCLUDING THE 1995 CHEVROLET AND GMC S/T MODELS. *TT
0306040142003-04-15. Service bulletin. OIL PRESENT AROUND TURBO AREA, OIL LEVEL LOW, OIL PRESSURE GAUGE MAY DROP. *TT
0206040602003-03-28. Service bulletin. AUTOMATIC ENGINE SHUTDOWN FEATURE. *TT
0206010242002-10-09. Service bulletin. ON CERTAIN VEHICLES, SUCH AS THE CHEVROLET AND GMC WT 5500 MEDIUM DUTY TILT CAB MODELS, THE ENGINES MAY EXPERIENCE ROCKER ARM DAMAGE OR ROCKER BRIDGE DAMAGE FOLLOWING OVERHAUL OF THE CYLINDER HEAD IF THE VALVE BRIDGE STUD INSTALLED DEPTH IS INCORRECT. *TT