ss00

The needle on the stock voltmeter on the dash of my '89 Iroc Z (TPI 305 5 speed) indicates either just above, or in the red discharge zone when the engine is running. This has been happening intermittently for over a year. Recently, the needle is in the red zone just about all of the time. The alternator is new and the battery is definitely being charged because I can drive anywhere and the car always starts right up. Also, when the engine is not running, the voltage across the battery terminals is about 12.8V and when the engine is running the voltage is about 14.5V. Are the gages known to go bad on these cars? Is this likely a wiring issue? Has anyone else had this problem and if so what solved it?

95LT1conv

start the car and diconnect the battery while the engine is running. while it is running test the output of the alternator while the battery is diconnected. if you get 12-15 volts from the alternator than it is probably a bad gauge

87DJP2001

You are getting indications of a alternator going south. The battery is running the car when you are not charging. If it been a while be prepared for a tow from the side of the road one of these days.

ss00

Fixed it. The problem was a bad connection at the back of the gage.