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Discussion Starter · #1 ·
Ok, took Steve's advice and confronted the problem using Haynes, service manual, a test light and a multimeter. Previously I had thought it was the PCM causing the problem, but after some work done today, and reviewing the schematics again, I caught a commonality between the problem.

As I was chasing the bug through the key ignition harness, the problem crept up again. As it did this, I was was standing next to the driverside front fender and I heard a few relays clicking on and off. After popping the fuse panel, I found that the relays clicking were the Fuel Pump relay, and the PCM Power relay. The common link between them is wire 37 Y running from 20A Fuse 16. One problem that I have had before, is that the previous owner had used fuse taps in various places, and it deformed the contacts in the fuse block. Does my theory seem sound or am I barking up the wrong tree.
"I woudl test the theory for myself, but Im at work, and won't see the big pig again till tommorow."
 

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Discussion Starter · #2 ·
Going through the schematics, the relay's power is hot in start/run. Circuit 16. Feeds power to the Instrument cluster, warning chime, TCS, and Fuse 22.
22 feeds power to ICM, Radio cap, Coil, Distributer, and Terminal 85 of the PCM power relay. What I can't find is the trigger. The relay will switch on and off almost like a breaker that is reseting itself. It will switch on for a second, then off. It will do this a few times. Or it will just never turn on, or stay on for a few seconds till it shuts off again. From what I am reading, the only real switch is the ignition switch which I have bench tested and it was fine. Plus nothing else on 16 is showing the same problem, so the problem exists after splice 206. I tried swapping the relay with another, and it did the same thing. I would think that if one of the four components "ICM, Radio cap, Coil or Distrib" were shorting to ground and draining all the power, it would blow fuse 22 which is between this side and S206. Im at the point of just giving up and taking it too the dealer.. "as soon as I can afford it of course"
 

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How is the relay's ground? Perhaps the ground that trips the relay is intermittent.

Put your test light on the + side of the relay's coil while this problem happens and see if the voltage is intermittent. If the voltage to the relay is steady, its a ground problem.
 
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