I just got a new batter by the way (3 weeks ago)

I drove my car the other day (without dash or any instrumentation) , and when it got dark, I turned on the headlights. The second I turn on the headlights, my engine starts reving lower and lower, as ifmy alternator is busted and my batterey is going dead. The second I turn off the lights, everythihng is back to normal. Now that my car is in the garage, it wont even start for shit. Everytime I try it makes a "click click" noise. Someone please help, what have I done?

Do your headlights or anything come on when your car is off?

Very wierd...definatly sounds like your altenator is going. If you're going through a battery in 3 weeks, then its not being charged.

That "clicking" noise is probably happening becuase the starter solenoid is trying to close but it doesnt have enough power. Hopefully your alt is still warrantied.

thanks, any of you guys know any diognostics tht I can run to find out the problem?

Originally posted by DCastillo
thanks, any of you guys know any diognostics tht I can run to find out the problem?

Check the charge in the battery, if it is not charged then get a jump from someone and take a ride around the block then check the charge again if it didn't charge back up it is probably the alternator. If you can't get the car to start at all, or it runs a little and then dies even after having someone give you a jump, then your battery is probably the problem.
I'm no expert that is just what I would try.

I'm almost positive that the click click sound is your ignition switch. This is good that you have this sound because an ign. switch is more time consuming than any other thing related to this problem. If you're going through batteries, more than likely it's your alternator.

good news, found out the batterey had just died. I charged it for 45 minutes this morning, and mechanic said everything was ok.