battery or alt
 

hey guys I m having a problem I dont know if is the battery or my alt but when I turn my car on and let it set my voltage gauge goes down and when I push the gas it goes up again and if I have the door open for 5 min my car dont want to start someone please

RE: battery or alt
 

your alt is discharging and draining the battery in the process. it might have even killed some of the cells. replace the alt, and see what happens. if you still have starting issues, you have dead cells from the alt and need to replace the battery.

RE: battery or alt
 

I do that and thanks

RE: battery or alt
 

whooooooooa, don't just go replacing things!!!! that's BAD.

batteries are EXPENSIVE, alternators are MOOOOORE EXPENSIVE!!!!

so please, if your car starts for now, take it to autozone or somewhere to get the battery and alternator tested. its free or really cheap, especially when compared to the price of an alternator or battery. you may go replace the alternator and find that you had a frayed ground wire -- easy fix coulda saved you $150 or 200. and a corroded battery terminal could cause plenty of intermittent electrical problems.

so just take it somewhere and get it tested real quick before you get the wallet out!

RE: battery or alt
 

i agree with getting things tested, as i am a tech, but think about it. bad ground wires would produce constant discharge, not just when its idling. if the alt goes up in voltage as you increase RPM, its going bad.

RE: battery or alt
 

I had to do a test today....turned out it was the guys alt....

But definatly get it tested first.

RE: battery or alt
 

thank you guys

RE: battery or alt
 

Alternator voltage is supposed to go up when you increase the RPMs to above idle. I bet his alternator is fine, and his battery needs to be replaced. Either that or his terminals are all caked with deposits, and not allowing good conductivity through the cables.