Another Charging Issue...

[STIZZANG]

Hopefully someone can help me out here because I'm about to dig deeper!!!

I just bought a 97 GSX (5-Speed) and it had a bad alternator to begin with. So I replaced the alt AND battery both at the same time! Fired the car up, and it appears to run great, shows a charge at idle even with all loads on! Now for the fun part...when the car is being drivin, it is making no charge and running straight off the battery which lasts approx 15 mins...but as soon as it comes to a dead stop, it starts to charge while @ idle! I have revved motor to approx. 3,000-3,500 rpm's and checked for a drain but I can NOT find a drain! The fuses all check out ok! Anybody out there had a problem like this or could recommend a good starting point to check into?? Thanks for your help in advance!!

 

[STIZZANG]

anybody??

 

[Doug99RS]

Let's start somewhere simple. Power and grounds. Do you have a test light and multimeter?

 

[STIZZANG]

yes to both! i'm thinkin i have a pretty good idea of what the problem could be...from other sites the members have given me a few good places to check...i will post my findings asap!

but any other idea would be VERY helpful doug99rs

 

[Doug99RS]

Put the meter in to volt meter mode and check from battery positive to the big positive lead on the back of the altenator. See if your meter shows any voltage going through it. You could have high resistance on the charging circuit that only shows up when loaded. Do you have a check engine light?

 

[STIZZANG]

nope no check engine light! when the batt. runs out though the ABS light and SRS light kick on which is normal! soon as the car is parked the alt. charges and they shut off!

 

[Doug99RS]

nope no check engine light! when the batt. runs out though the ABS light and SRS light kick on which is normal! soon as the car is parked the alt. charges and they shut off!

This is correct. The ABS pump requires alot of current to stay alive and it's the first thing shut off when you lose charging voltage.

You have verified battery terminal cleanliness, altenator connections and cleanliness as well right?

 

[STIZZANG]

yes. battery is brand new...alt is brand new as well! clean both batt. cable terminals and still no help!

 

[Doug99RS]

Is the belt tight too? Higher RPMs could mean more slippage.

Back to the electrical side of things. Have you done the voltage drop test from the battery to the altenator?