Alternator Problem, I Think

[W0rp3D]

Lately my battery has had less and less power to start, never has not started but there are the signs of a problem ahead, i assumed either the alternator or battery, tonight though, when i was driving home the alt light would start to come on, the higher the revs the brighter the alt light, if i am correct the higher the revs the more power it should put out not less?

Has anyone had this problem before and what did you do to fix it?

Any suggestions would be appreciated.

[blind_elk]

Check the tightness of the fanbelt.

Check the output of the alternator at various rpm (there should be numerous threads describing the procedure, but I just tried a search, and the search engine leaves A LOT to be desired - didn't find one of the ones I thought I should). Basically, measure volts across the +ve and -ve terminals of the battery. At idle, should be around 14V. As you increase revs, should remain 14V. If volts increase, then the regulator is bung. And the resultant overcharging will eventually kill the battery.

If the regulator is ok, try turning on the headlights - a healthy alternator should be able to maintain 14V at idle.

Also, you should consider the age of the battery - they don't last forever.

[d00dz]

Check the tightness of the fanbelt.

Check the output of the alternator at various rpm (there should be numerous threads describing the procedure, but I just tried a search, and the search engine leaves A LOT to be desired - didn't find one of the ones I thought I should). Basically, measure volts across the +ve and -ve terminals of the battery. At idle, should be around 14V. As you increase revs, should remain 14V. If volts increase, then the regulator is bung. And the resultant overcharging will eventually kill the battery.

If the regulator is ok, try turning on the headlights - a healthy alternator should be able to maintain 14V at idle.

Also, you should consider the age of the battery - they don't last forever.

Interesting..

At idle mine was 14.5v, as revs go up it would go up too. When lights are on it dips to like 13.9volts.

And last nite my car just conked out. If only I had read this thread..