I am having problems with my 85 Trans Am. It does not start and when I jump it, it runs for a while and then stalls. The longer I charge the battery before I start it, the longer it runs. That's why I assume the battery is fine and I either have a problem with my alternator or the wiring.

I changed the alternator with another used one I had, and the problem is still there. It might be that this alternator is also bad, but I don't think it is.

Has anyone had a similar problem? Could it have to do with the wiring? If so, where should I look for the problem?

 

What type of instrument cluster do you have and is your engine carburated or fuel injected?

 

is the wiring at the alt modified ?

take care to local small time battery shop they will check the alt real quick with car running for free

i do this all the time with my vehicles,

had to yesterday with the 84 impala in fact, the 4 year old battery died, so i jumped it and drove it to the shop to get another battery and to have them check the alt output real quick, alt is fine, batt was toast




how old is your battery ? what is the second digit on the round white sticker on the battery ? it will be 0-5 most likely and the code will be like D4 or something just like that

what does you guage read with engine idling
does the needle fall when you turn on something like lights or heater fan motor ?

good luck

 

Thanks for the fast reply. The engine is TPI. The instrument cluster is the standard one that came with the car, I think. It has the three circular sections of equal size. I don't know how else to describe it. Why is that important? Could the problem be caused by the instrument cluster?

Please, somebody help me. I need my car to run by next weekend.

 

The instrument cluster plays a role in this because of the wiring and circuits involved. If you have a standard cluster there is a diode between the alternator and the voltage indicator that could be bad. With the gages cluster there is a 10 OHM resistance wire between the ignition switch and the alternator. With the electronic cluster there is a diode between the alternator and the printed circuit board on the instrument cluster that could be bad.