Hi all. I bought a 93 camaro Z28 last week. I was driving on the highway, turned on the A/C and the radio, and the dials started going crazy; the speedometer was pointing to the wrong speed, the rpm gauge was going up and down, and the dashboard light dimmed out. When I turned off the A/C and the radio, everything went back to normal. Any ideas?

 

sounds like either a voltage regulator or the alternator has gone/is going bad.

 

That makes sense.. thanks alot! do you know where I can get one for a good price?

 

Did you hear any strange or squealing noises when that happened? If your A/C compressor is bad/locked up, turning on the A/C (engaging the clutch) could make your serpentine belt stop dead in it's tracks, which then also stops the alternator from spinning. The first thing you should check under the hood is the A/C clutch and serp. belt, while someone else turns on the A/C.

 

sure sounds like a bad connection at a positive or a ground. could also have a short in the a/c clutch or wiring. could try unplugging the a/c pump. anyways check your grounds, one on the front of the motor on the driver side under the coil unit, one on the passenger side in front of the starter, one under the motor mount on the passenger side. also check and clean the positive and negative power junction boxes (one red, one black small plastic boxes) on the passenger side fenderwell. take the wires lose and wire brush the heck outa them, while your at it take the battery cables lose and brush the cable ends and battery posts. you also have a couple of main grounds inside the car.

 

I didn't hear any squeaking noises at the time. The AC compressor is new nd it works. I will check on that wiring tho. thanks

 

Sound like the dash ground is loose.

 

So if I check the ground connection and fix it, is it still possible the alternator would need to be replaced? If so, does anyone know what make is better to get?

 

you could take the alternator out and have it tested at the local parts store. i would clean and check all connections first and see what happens.