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The voltage spikes started about 3 years ago. It seems to be intermittent and only last about 2-5 seconds. It would cause the gauge to max out at 19. It causes the headlights to shine brighter and the whippers to go warp speed, so it's not an instrumentation issue. When the problem started I checked my battery terminals and tested the battery, those checked good. So the next logical step was to replace the alternator. I replaced the alternator and the problem still continued but not as often. Fast forward to a month ago, I noticed that it would spike a lot more often and for longer durations. I was coming back from the lake 2 weeks ago and all of a sudden it would die when I slowed down to make a turn. It started up after about 10 seconds and would drive down the road for a little bit then died again. It would start again after 10 seconds. I was able to limp it home. RPMs at idle is between 500-700 and it seems there is no sputtering or misfiring. The codes I pulled where, 41, 46, and 54. I remove the wire harness from the battery to the starter/relay box and the battery's negative cables and hooked up the meter and bend the cables to simulate road movements, the meter read constant 1.5 ohms. I put a junk yard distributor/cam position sensor and it seemed to fixed the issue. I drove it all over country roads and the highway for about an hour. The next day I drove to the lake, about 45 minutes from home and it started to surge half way and died when I made the turnoff from the highway to the lake. Same as before it would die when I slowed down. Limped it home again. I pulled the alternator out and it tested bad, replaced it. I shot the wires from the alternator to the PCM, ignition coil, battery and the ground. All of them reading less than 2 ohms. I reseat the PCM connector and hooked up the new alternator and test drove it. It surged then died about 30 minutes into the test drive going up hill. It continued to die when I tried to climb the hill. I was able to get it turned around and coast it down the hill. It died in neutral while coasting to a stop sign. Got it home and pulled codes(41 and 54). Here's the recap.

Trouble shot:
Battery cables
Alternator wire harness
Cam position sensor connector
Fuel pressure, reading 32psi w/regulator 41psi without.
Swapped the abs relay with the shutoff relay

Replaced:
Alternator, twice
Battery about 1.5 years ago
Distributor w/cam position sensor
 

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Aside from the normal ground wire checks. The voltage regulator is built into the ECM.

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