dazebreak

In car test at parts store said battery OK, just not charged - after driving 60 miles on highway, battery light came on after 40 miles. History:

Maybe unrelated, but a couple days before + battery connection loose caused no crank (no connection). Tightened old loop best I could.

Drove 850 miles over 15 hours and last 20 miles on freeway battery light flickered on and off. Got off freeway, it began to stall in traffic. Got shim from parts store for terminal due to stretched out connection. Tightened down and drove around, still battery light on.

Bought a battery, because the one installed was the physical wrong size. Battery light on at low RPM. Went to parts store right away. Parts store tested battery and system. Low charge and alternator failed regulator test. Told me to bench test. I removed and had them bench test. The alternator PASSED. Noted belts were shot, replaced belts. Made sure alternator belt tight.

Checked grounds and positive battery connection. Installed alternator and drive belts. Drove 20 miles, no problem. Parts store checked system while in car again, it all passed yesterday.

Today drove 40 miles, battery light comes on under 2500/RPM. Parts store tested system again, said alternatively failed regulator test.

How does it work, with the RPM and the regulator? Could the alternator be intermittently bad? Could a weak connection cause this? What else can I test? I did the test in the book that shows the WHT/BLU wire OK. That goes from the light to the L side of the regulator. The large wire on the alternator is the ground, correct? Where's the other end?

Anyway, help please!

Should I just try a new alternator?

dazebreak

Broke down... must be alternator

rollinmyda

iTrader: (19)

Yep, if it was failing and passing randomly you were already on borrowed time before it completely failed. Had it happen to me personally before. Started acting up as I was leaving town. I was getting an intermittent battery light. Made it where I was going, but the alternator/car died literally as I was pulling into a parts store. I jumped it and it passed their test but when I asked them to test it again immediately afterwards it failed. Replace the alternator and you should be fine.

wunfstgsr

Alternator.