I've got an 84 Z, 305 (LG4) with only minor mods. My check engine light stays on all the time. I've decoded it using the jumper wire and I get a code 54, the Haynes manual says this is a M/C solenoid. I even took it to the chevy dealer and had it decoded and they said it was the M/C solenoid. I changed the solenoid, the light still came on. The carb was rebuilt, the light still came on. I've adjusted the idle mixture and the car runs good, but the light still comes on. I can't see anywhere that the wire is broken or stripped. Every time I do something, I unhook the computer to clear it out. When I hook it back up, the light comes back on as soon as I start the engine. Has anybody got any ideas how to fix this?

 

Goto Autozone and ask them for a print out on how to diagnose the code 54 for your car. It will give you step by step prcedure and help you eliminate some things.

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89 Trans Am Turbo 3.8L All stock 43,000 miles #1053 of 1555

Past Thirdgen:
86 Trans Am w/ built 355TPI with SLP goodies and too much other stuff to List. One sweet *** car, wish I would have had a good enough Job to pay insurance on three cars so I could keep it, but for a 89 Turbo Trans Am w/ Low miles, I think I made the right choice!