ShovelMan

I recall seeing a pic that says "Check voltage on battery, alternator" etc. It gets posted here a lot whenever a person claims a problem with their optispark. I can't find it. Need to troubleshoot my alternator.

If anyone wants to take a crack at my issues:

- Driving in the rain. SES light popped up.
- Voltage dropped to the yellow-diagonal lines section (below 10?)
- When I use turn signal, the speedometer fluctuates about +/- 5mph
- Tachometer is just the same
- New Battery
- AFAIK, the alternator is probably the original alt the car came with (1993)

SS RRR

iTrader: (2)

Don't get it tested. Test it yourself. With the engine running, put a voltmeter to the charging wire that leads to the battery and a ground source and see what the voltage is. It should be a STEADY 14.5 volts. If it fluctuates the alt. is bad. If it's lower than 14.3 volts then most likely it is bad.

ShovelMan

I have two readings:

Using a Fluke 115 from work, I put the probe on the red wire on the Alternator's square post and the black wire on the battery's black/negative post. If this is the wrong way to do it, please let me know so that I can test it again.

Voltage (AC), I got 12.65. Voltage (DC), I got 0.364. Either that or I made a mistake and got the numbers mixed but both of the numbers I got back were 12.65 and 0.364 with no fluctuations with engine running.

ShovelMan

The alternator has been replaced with a rebuilt Carquest one from AAP. Looks like the core used to rebuild was a REMY USA. Looks sharp, but out of place in my weathered engine bay.

Problem is solved. No more low voltage triggering the SES light anymore!!!

curacaoz28

icm or opti..... (93 non vented )

ShovelMan

93 bone stock but my Optispark is vented. I don't have the hose that goes from the opti to elbow. I don't know if I should plug the vent on the optispark.