Vegas Smith
20+ Year Contributor
- 5,191
- 3,108
- Dec 2, 2002
-
Houston,
Texas
Hello all, just got the car put back together with a bunch of new mods (didn't touch the electrical system). The car is running extremely poor and it appears to be caused by sub-12 voltages. Battery takes a charge and sits at 12.5-12.6 but drops to about 11.9 when the car starts. I noticed the battery light bulb was not glowing and that's part of the charging system so I replaced it with a known good bulb and this did nothing. The battery light still doesn't light up at all even with a known good bulb. All wiring to the alternator ( Saturn 200a with about 100 miles on it) is in great shape and was working perfectly prior to the car going down for a few months (putting out 14.5 v etc).
I've also replaced the 10a "gauge" fuse that's in the charging circuit. Voltage at the alternator stud is about 11.9 when car is running. Belt tension is adequate. The two alternator wires are showing oscillating voltages when car is running which leads me to believe the alt-relay is good and sensing fuse is good. Replaced alternator 80a fuse as well.
The only think I can think of is right before the car was put down for new parts, my jay racing alt-bracket broke and I had to drive home 3 miles with the alternator sitting on the subframe with the belt disconnected. I'm wondering if the alternator burnt out somehow because of this? Maybe because I left it plugged in while I drove home?
I've also replaced the 10a "gauge" fuse that's in the charging circuit. Voltage at the alternator stud is about 11.9 when car is running. Belt tension is adequate. The two alternator wires are showing oscillating voltages when car is running which leads me to believe the alt-relay is good and sensing fuse is good. Replaced alternator 80a fuse as well.
The only think I can think of is right before the car was put down for new parts, my jay racing alt-bracket broke and I had to drive home 3 miles with the alternator sitting on the subframe with the belt disconnected. I'm wondering if the alternator burnt out somehow because of this? Maybe because I left it plugged in while I drove home?
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