what would cause a voltage dran (or cause the alt. to stop charging) after the car warms up but before the cooling fans turn on?and only when i use more that 2 acc. or more at the same time. ive replaced the battery,alt. and battery cables. ive checked the fuses to make sure they are the right amps. ive checked under the dash for bad wiring and replaced some connectors in the engine compartment. still no clue as to what is causing it.just last night proved that. when i left work it was raining so i had the lights,wipers,radio,defrosters,a/c defrosters. and it was just fine but as soon as it started to warm up down it went.

any help would be very very great ive been working on this problem for awhile now and its driving me nuts. but if i have to ill send it to a shop.

sorry for being so long but i wanted to give you guys as much info as possible

thanks in advance

mark

 

I'll give it a shot since you haven't had any replies. I had the same problem in two of my other non thirdgen cars. Your idle might be too low and in too much stop and go driving, your engine isn't spinning the alternator fast enough to recharge the battery fast enough to keep up with the drain from the use of all the accessories. 100-200 rpm can make the difference between keeping the rechange/discharge ratio equal or not.

 

Just a thought- A bad wire or connection can cause a lot of resistance and heat.Heat will increase resistance,making it even worse.If you have an old corroded cable or poor connection which is already presenting a lot of resistance,then the heat created from the excessive resistance and heat from the motor(after warming up) will only make it worse. Maybe the battery isn't getting the charge it needs due to a bad cable.If you've replaced everything you can think of,then I would start checking ALL cables,connections,etc. Like I said,just a thought to try and help.

 

What style of alt. did you put in the car (I.E. 10si,12si,17si,etc.etc)
the smaller alt's. do not put out as much current as the larger style alt's. if you put in a 10si or 12si you won't get as many amps as you will out of a 17si. (the rated amperage of the alt. I.E.--85,94,105,etc,etc. is based on nominal operating rpms, not idle) try to find out which style you have and post it,

PS. I have found that autozone and advance only sell the 10 or 12 si alt's (at least in my area) and most of them cannot tell you which style it is anyway, I found a 105 amp 17si at napa.

 

alt i know is a 105 amp. as far as the 10 si 12 si etc. i have no clue ill ask the parts store in the morning.

thanks

mark