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HOMESERVICE MANUALSPONTIAC1991FIREBIRD FORMULA, 5.0 F, STANDARD, M39REPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 6 (ENGINE CONTROLS - BASIC TESTING)BASIC IGNITION SYSTEM CHECKS (C-4)C3I (3.3L & 3.8L)SPARK
1991 Pontiac Firebird Formula, 5.0 F, Standard, M39

C3I (3.3L & 3.8L): Spark

1991 Pontiac Firebird Formula, 5.0 F, Standard, M39SECTION Spark
WARNING: This page does not describe the selected car, but rather 39 other vehicles, including the 1992 Saturn SL2, 1992 Saturn SL1, 1992 Saturn SL, 1992 Saturn SC, and 1992 Pontiac Sunbird. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect tachometer wire if equipped. A shorted tachometer will prevent vehicle from starting. Disconnect cam sensor, and attempt to start engine. If engine starts, see appropriate cam sensor trouble code in appropriate G - TESTS W/ CODES article in this section. Check for adequate spark using Spark Tester (ST-125). Check for spark on plug wires No. 1, 3 and 5 (one at a time). Leave matching plug wire connected while checking for spark. When removing spark plug wire from spark plug, twist and pull on boot. DO NOT pull on wire.

RENDER: 1.0x

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