My 91 s10 4.3
5 Answers
What shape is the wiring harness in? Electrical grounds? How about voltage spikes from the voltage regulator or alternator?
Have replaced wiring in harness that had burnt through and crossed. When it's about to happen I see the voltage meter in the dash spike. I have never seen spikes when I put a meter to it. But the voltage regulator and alternator are two things I haven't replaced yet.
And the voltage regulator comes with an alternator if I buy a new one right?
A spike is never good, and you should also check for minimum voltage from regulator when switching lights and other functions on. If it dips and doesn't come back up that can also cause problems. I would also check battery and engine grounds are good, wire brush the grounds so there is good electrical contact. Check for voltage drops between battery, starter, and alternator. These should all be between 0.1 volts of battery voltage. With the engine running you should have between 13.5 and 14.5 volts. Keep checking voltage as you turn on electrical loads, such as lights, heater fans, rear defogger, etc. The voltage should maintain around 14, if it dips too far then regulator is bad. You should not see spikes either, spikes can kill computer modules. If all this check out okay, you may need to start looking into modules, like the instrument cluster one.
