In my 93 Firebird Formula Ill be driving it and the volts are always showing really low on the gage, after driving on a fully charged battery for around 20-30 mins the car would die. I just put in a brand new battery and alternator. Any suggestions as to what else could be causing this?
thanks for the help
sounds like the alternator, but if you just replaced it than maybe double check the connections. You could also run it to autozone to test it…
Bad ground probably. Take a pair of jumper cables and attach the negative wire to the negative post, and the other end of the negative wire to a good ground point on the block. See if that changes the volt meter reading with the car running. If it does you clearly don’t have a good enough ground going between the engine and the battery.
If it isn’t that start checking the heavy power wire coming off the alternator and make sure it’s ok.
Bad Alternator; or bad connection on the Alternator. Make sure all the wires are plugged into the alternator properly. The plug retainer clip busted off mine a while ago and it would fall out and do something similar.
I agree with all of these guys and another check that you could do is to full field the alternator by bypassing the voltage regulator. Voltage should shoot up if it does then you have a bad voltage regulator.
check the resistance of the wiring between the alternator field coil terminals and the regulator/ecu. check the resistance of the wires between the alt positive post and the battery and the battery ground and the casing of the alternator.
make sure all the terminals are clean and without corrosion.
you can also disconnect the field coil wires and probe the connector with a meter and see what the voltage is with the car running on just the battery. it should be something close to 12v as the ecu/regulator is trying to increase the field current as the voltage that it measures is low.
probably the alt though. parts store alts are hit and miss.
Brian
I went through 3 reman alternators in like a year and a half.
Check your main Fusible link for the Alternator, thats what was wrong with mine.
Replaced bat. and alt. and after 35 minutes the car would just die. no charge was being held through the circuit.