Uugh, electrical problems...

[michaelw]

Rather ubruptly, my 87 3.2 has developed an electrical problem. The 2 year old battery which has never once had a problem, now will not start the car. I had the alternator redone last summer as the alternator light started pulsing, but since then no problems.

First the alternator does not illuminate once the car is running (from a jumped start) and is registering 12.95V while checking across the battery. Before the start it was reading 12.00V. I checked the following morning and the battery read 11.87V and this afternoon at 11.85V. What's up? If it's draining, it's draining very slowly.

Thanks,
Michael

[CamB]

Batteries sometimes don't last very long (in my chequered experience with them).

12.00v is pretty dead (should be 12.5 ish). I you have a charger you should give it a full recharge and see if it holds it.

12.95v when car is running is too low an output for the alternator as well (should be 14.4ish). I think you might need to get the alternator and regulator checked (and may need a new battery too).

[6 Shooter]

If you take your battery to a shop to load test it, make sure that it is fully charged before testing. Testing is done with a VAT (voltage-ampere test). The amount of load is based on the amp-hour rating or the cold-cranking amp rating. The battery is loaded at 3 times the amp-hour rating or 1/2 of the cold-cranking amps for 15 seconds. Battery voltage should be at least 9.6 volts. HTH.

[slakjaw]

dood

while the car is running test the voltage between the positive and neg batt terminals,, then check it between the pos terminal and a frame ground or some other good ground. i just did the same thing to a car yesterday and all it was,, was a bad ground strap.

I hope that helps you!!

LATE-ER

Kyle
71 911

[michaelw]

Thanks - guys! Will definitely try to the ground strap test.

Michael