hey my car has always done this and i was just curious if anyone has had similar experiences. when sitting at idle at a stop light my headlights are kinda dim but when you hit the gas and start moving they brighten right up. the alternator is a year old and its got a gel cell battery. just thought it was kinda strange because no other car ive ever driven does this.

 

whats it idle at? The idle just may need to be turned up a little. I don't know how and my only assumption is thru burning proms but there should be another way...i know when my truck developed that problem i turned it's throttle position sensor up a little, but i know that probably isn't correct.

 

im pretty sure the idle speed is fine its pretty low but its smooth the car never ever dies or anything it runs great. i would say 700 rpm in neutral?? ive never really looked but its low. ill check for sure tomorrow.

 

What is battery voltage at idle? How old are your wires from alternator to battery and ground cables? What is voltage at the headlights compared to battery voltage?

 

i know the battery voltage at idle is about 13.5-13.7 because ive checked it before. as far as the other voltages go i dont know. ill have to check. all wiring is stock but in excellent shape. the car has been in the family since new and was always garaged up till about 5 years ago.

 

i checked it today on our machine at school.. charging at idle no accessories on it was about 14.4. it was like 13.5 or 6 with the engine not running , but heres the wierd part. at idle with all accessories on including a/c, the charge gets way dragged down... to about 12.2 volts. 2 volts is a lot for it to be drug down to . . i think the alternator is going bad. thoughts ?

 

my car does this also and my alternator is well, not sure but about a year old also. since my cc carb is just about shot the car idles at about 1k cold and 750 at operating temp. one thing ive notice recently though since it started getting cold is that on occasion during warmup the alternator seems to completely stop charging even while driving. My guess would be that the alternator is starting to showing its age

 

I've got the same problem. Mine wasn't doing it when i first bought the car. I posted here about it. Haven't found my problem as of yet. Had 2 alternators already, and even had the one tested and tested fine. So, i'm not sure what the problem is, but i need to find it. If you find a solution, let me know. I'll do the same, when i can get time to work on it.

 

mine does the same thing.I just put a new altenator on and it still does it.I think maybe it needs a higher amp altenator.My charge does drag down some though.It really does it bad when I have all my acceseries on,especially when my fog lights are on at idle.I did find a bad wire going from my alt.Which means my alt wasnt bad.I realized it afterwards when my battery kept dying.when I fixed the wire the battery started getting charged again.the pully bearing on my old alt. was going bad(sqeaking and loose)so I didnt take the new one back.I wonder if I still dont have a bad wire or bad ground.

 

same issue here. I never really worried about it though, they don't dim enough for me to think something is wrong, but you can definitely tell when they really light up when the car is moving. I've thought about a higher amp alternator...