battery question!!

[kbsonicstang]

I just got a new battery last week, and put a new altenator on in september. But when I drive to town it will stay around 14 amps, but when I get to a red light, or stop at a stopsign the amp meter drops to 11 or 12 amps, and almost dies. Also just put a new battery cable(hot) on it when i got the battery. The car is a 88 mustang 5.0L. What could be the cause of this problem?

 

[blownfox]

Do you have an underdrive pulley on the altenator or a E-fan? Also I always notice a charging problem with my stock replacement alt. I upgraded to a 140 amp alt from a 94 and up mustang GT and that problem is long longer a problem.

 

[kbsonicstang]

Do you have an underdrive pulley on the altenator or a E-fan? Also I always notice a charging problem with my stock replacement alt. I upgraded to a 140 amp alt from a 94 and up mustang GT and that problem is long longer a problem.

no all stock pulleys and fan. also did you car amp meter drop down that low when you came to a stop?

 

[blownfox]

Yes...that was when I had a stock alt 65 amps (no U/D Pulley) and a flex fan. That would always happen when running the heater or AC and headlights.

Now with the 140 amp alt, I can run everything including my E-fan and it does not move. This is the first time I've every had a battery last longer than 2 years.