I might have a problem or it might be normal, i dont know. it was really hot today, like mid 90's with high humidity, and after i had been driving my car around for a while, a 98 T/A, with the AC cranked i noticed when i was sitting idle, my voltage had dropped to around 10, right on the edge of the orange warning zone, however when i turned the AC off, the voltage jumped right back up to 12, and when i was moving and had the rpms up the voltage was higher, and closer to 12, but when i was just sitting idle it was really low again, and also my oil pressure was kind of low, it was down around 20ish, is this normal, and just symptoms of the heat or is something going wrong?? Please help I'm kinda worried. Thanks.

 

Do you have underdrive pullies?

Do you have an aftermarket stereo/amp setup as well?

It's possible the battery is weak and the alternator is begining to fail.

Could also be a seized A/C pulley/clutch.

That's a good list to start with.

 

the oil pressure yes i think (hot oil thins out)... see if the belt is slipping maybe when it gets older and hot it starts to stretch, see if it does it cold when you first start the car

 

i do have an aftermarket stereo and amp. i doubt it is a seized ac pulley clutch, because ac still works fine, and the belt is in good shape. when the car is cold the voltage is way up around 14ish, but when it gets really hot it drops. the belt is a shitty gatorback belt. maybe that's the deal.....

 

mine does all that except the oil pressure crap..