Last Thursday I replaced the alternator on my SS. On my first drive after replacing it (voltage was great, 14+ volts on the gauge), I got on it a bit and noticed my "check gauges" light was flickering. Not on solid, but flickering. Whenever I let off the gas, it stopped. I watched the gauges closely but nothing looked out of the ordinary (including voltage which was a solid 14+). Today however, I got on it again and the "check gauges" light came on solid, and I noticed that my voltage had suddenly dropped into the red. I've been watching the voltage quite a bit since I just replaced the alternator and I'm certain it dropped immediately during my hard acceleration, down to the top of the red zone. The car ran fine though and I was only about 100 yards from the parking lot I was headed to, so I drove it there and stopped, and felt no problems with any systems, no dimming of lights (of course it was daytime so there wouldn't be much to dim, but my aftermarket CD player looked completely normal). I rolled up the driver's side window (power window) before I shut the car off and it went up like normal. I needed to get to work so I couldn't investigate it right away, but I did pop the hood to make sure the belt was still on and it is.

My questions are these: This doesn't seem like an actual loss of voltage to me for several reasons. The car acted normally and if it had really lost that much voltage, wouldn't the computer have had problems and caused the car to run rough? Wouldn't I expect the window to not roll up normally? Also, considering I have an Optima battery that's less than a month old, even if my new alternator up and died on me, wouldn't I see a gradual decrease of voltage as the battery wore down, rather than instantaneous? Does anybody know what the small wire that is clipped on to my alternator is for? It may go to my scavenge pump (part of the turbo kit) but what I'm thinking is maybe it came loose or was cut (if I left the wire sitting in the wrong place). How does the car sense how much voltage there is?

TIA.
-Ty

 

Anyone?

 

Ty it might help if you turned off your 8000 watt stereo system. :p

 

There are two wires - one for the battery, the other goes to the PCM. Check your wiring, sounds like something is loose.

 

Use a voltage tester to check the voltage of the battery alone, and then check how much the alternator is putting out, if any. Maybe you got a defective piece.

 

Thanks guys. I bet it's the wire to the PCM. I'll find out for sure on Tuesday when I'll have time to look at it.