When my car is either off or at idle,(100-400rpms) everything inside my car from the fan to the gauge lights and even the headlights are either dim or running at low power yet once the engine is about 600-1000 rpms,somewhere around there, everything goes to normal? I've heard that it could be grounds, if so how would I check them and where are all of them at?

 

Your alternator is under load when running accessories....it's normal. If everything is too dim or slow, you may have a weak battery, alternator, or both.

 

I just thought that it was wierd that when the car is off but the key is in the on position the headlights and fan run slower than when I turn the car on and run the engine at a higher speed than idle. That being said, that makes me want to rule out the fact that it could be the alternator because it does the same thing whether its being used or not. Maybe it is the battery like your saying. But how would I tell if a new batter would fix this probelm without buying a new one? Can a run a test on the battery with a multi-meter?

 

Yeah, you need to see what the battery voltage drops to when it is under load. If it goes below 10 volts, you need a battery.

 

Yeah, you could run to any local autozone and they should test the battery for free. But you also mentioned that your lights were dimming around 100-400rpm range. In all the cars that I have seen, unless being a diesel, your car is bogging bad or about to die at those rpm's. Your car should be idling around 800rpm's under normal conditions. (just letting you know btw, im not lecturing you). Anyway, if you battery does check out ok, I wouldn't worry about because it sounds like everything is acting how it supposed to.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Okley_01 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, you could run to any local autozone and they should test the battery for free. But you also mentioned that your lights were dimming around 100-400rpm range. In all the cars that I have seen, unless being a diesel, your car is bogging bad or about to die at those rpm's. Your car should be idling around 800rpm's under normal conditions. (just letting you know btw, im not lecturing you). Anyway, if you battery does check out ok, I wouldn't worry about because it sounds like everything is acting how it supposed to.</TD></TR></TABLE>

Good to know. I haven't had this car too long and I always figured the idle was too low. I never bothered to look it up and see where its really supposed to be at. Thats probably why I have such a rough idle too. Anybody know how to adjust the idle an a b18b engine. (j/k i'll do a search later)

 

The fully charged battery will have somewhere between 12-12.8 volts. The charging system runs around 13.5-13.8. If the revs are too low, the alternator does not have enough amperage to run everything at full voltage. Once it picks up a bit higher, the volts come up to the setting on the regulator and everything comes up to speed. If yours is idling that low, I wonder if the idle system is working properly?