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Service bulletin 990601003

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 id605961
Published by NHTSA1999-08-04
Manufacturer's number990601003
Manufacturer's date1999-04-01
NHTSA componentENGINE AND ENGINE COOLING:ENGINE:GASOLINE

NHTSA's summary

CUSTOMER MAY COMMENT ON ENGINE KNOCKING NOISE. *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

Vehicles listed
CADILLAC ESCALADE1999
CHEVROLET C SERIES1996 to 1999
CHEVROLET G SERIES1996
CHEVROLET G SERIES1997 to 1999
CHEVROLET K SERIES1996 to 1999
CHEVROLET P1999
CHEVROLET P SERIES1996 to 1998
GMC C SERIES1996 to 1999
GMC G SERIES1996 to 1999
GMC K SERIES1996 to 1999
GMC P1999
GMC P SERIES1996 to 1998

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

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0406040882005-05-13. Service bulletin. REPLACEMENT OF CONNECTOR WHEN REPLACING FUEL TANK MODULE/FUEL PUMP MODULE. *TT
31212004-11-04. Service bulletin. EXHAUST VIBRATION RESONANCE OR MOAN. (2004-2005 GMC DENALI) *SC
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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
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