1992 GMC Sierra 92 GMC 4.3l code 15

J.STIEG

MEMBER
1992 GMC SIERRA

Working on a 92 gmc and it is running rough I have the CTS reporting abnormally low, how to troubleshoot. Getting code 15 diagrams would help. Trying to determine sensor or harness. Also what is the resistance value of the CTS when cold. Thanks

2 Replies

HMAC300

MECHANIC
48,601 POSTS

You really need a scanner to troubleshoot but see pics clicking on pic should enlarge a lot of those leaked coolant to wires so that may be problem and need a harness replaced which some came with switches. Rough running spray choke cleaner below tbi as that gasket had a high failure rate as well as soft hose going to map sensor, sucks together then map doesn' tread right.

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