Well, i just bought this 88 z28 for $500. Its in decent shape, but has some electrical problems.
It iddles fine, and the charging guage reads 13.6, then as soon as i put it in reverse or drive, it drops to about 8, then drops further until it dies.

Anybody have any type of advice?
thanks alot!

 

*Bump*
Sorry im just trying to get people to read this

 

I'll bet that the alternator is shot. Replace the alternator, and double check that all of the grounds and connections in the charging system are good and secure....

 

Just to add, a new battery wouldn't hurt either.....

 

i already tested the alternator, i know the battery isnt great, but that doesnt explain the actual problem....
any other suggestions?

 

The problem could very well be the battery. Actually, your battery and alternator need to BOTH be in top shape to work together. If the battery is bad, and even a new one can be bad, the car just wont run. Ask me how I know...Check and double check that the battery is OK, take it out of the car and take it somewhere reliable to have it load tested. A battery with a bad cell will draw too much power, or not even charge, eventually killing itself and giving you a No-Run situation. A bad cell in the battery will also prevent you from even jump-starting it.....again,,,,,,,,,,,ask me how I know....

 

If the gauge is reading between 13.6 - 14.5 at idle, this is normal. But if it drops under a load (in gear), then you're alternator (provided you don't have a volt leak) is shot.

If this is the case, then one of the bands inside the alt. might have snapped, causing loss of voltage after the addition of a load....

If it's the former, then you'll need a test light to check all you're fuses.... to make sure that there are no loose/cut/exposed wires causing voltage leak, but I doubt it, especially since it drops down to 8, then dies.

To me, it sounds like you're alternator. But this is obviously just my opinion.

(again, double check you're grounds, cables, terminals etc... the entire charging system)

 

one very easy way to check to see if the battery is bad, hook a voltmeter up to the battery, remove the fuel pump fuse or the injector fuses, have a friend get in and crank it over and if the voltmeter reads ANYTHING below 10 volts, its time for a new battery.

 

Even if it reads 12 volts, still have it checked. It may hold voltage, but not put out enough amperage to run things. Again, they have to all be working together, and be working correctly to give the end result.......a running car!