1995 GMC Sierra engine light on

1995 GMC SIERRA
198,000 MILES • V8 • 4WD • AUTOMATIC
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TSAUSTIN1614
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I have a 1995 gmc sierra with a 5.7 liter engine. When I start it up cold the engine light comes on and if I lightly press on the accelerator while in park, the tachometer goes to the red line. Also, the speedometer moves. After shutting the engine off 2 to 3 times, and restarting, the engine light goes off and it runs normally.
Jan 23, 2011 at 10:13 PM
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RASMATAZ
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Check engine light on

Have the computer scanned for code/s-you have a problem within the engine management system that caused the CEL to turn on-This is your starting point of diagnosis,finding out what's going on.
Jan 23, 2011 at 10:15 PM
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OBXAUTOMEDIC
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Hello,

To extract a trouble from the computer for diagnostic purposes, the Assembly Line Communication Link (ALDL) connector is used.

Ground terminals A and B with the ignition "ON" and engine not running. The system will enter the diagnostic mode. In this mode, the computer will display a 12, three consecutive times, by flashing the "CHECK ENGINE", "SERVICE ENGINE SOON" or "MALFUNCTION INDICATOR LAMP" or light. A 12 consists of one flash, a short pause, then two flashes in rapid succession.

After 12 is displayed, any stored trouble s will be displayed by flashing the "CHECK ENGINE", "SERVICE ENGINE SOON" or "MALFUNCTION INDICATOR LAMP" light. All s are displayed 3 times each then a 12 will repeat. In the diagnostic mode, the computer will also energize all computer controlled relays and solenoids.

Post codes.....
Jan 23, 2011 at 10:18 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.