I drive a 2001 Camaro Z28, all stock on it. By now she has passed 18,000 Miles ;-).

All of sudden I noticed that EVERYTHING electric has started to flicker when the outside temp is over 65-70. Of course, I took the car to a GM dealership and guess what: GM TAC says it's a normal condition as long as the alternator output is ok.

The "VooDoo" thing is that the issue is almost guaranteed to happen when the weather is warm-hot (over 70 degrees). It does not doing it all the time and it's hard for me to reproduce it at the GM representative. Now, even the ammeter on the dashboard flickers, the lights, the dashboard lights, everything. On top of that I've seen erratic ammeter needle spikes of +- 1.5 to 2V. This doe NOT happen when the engine is idle (bellow 1000 RPMs). At the same time I've noticed the car shakes when accelerating with almost the same frequency the lights flicker. Of course GM TAC says that's normal too. I changed the battery with a titanium one, 700 crancking amps (instead of the stock 525 one). I do NOT run ANY hi-amp audio, etc. It's just all stock!

Please help me with any ideas you may have.
Thanks in advance!

 

Despite what GM said, I'd try a new alternator. Sometimes a GM dealer will tell you this that or the other thing because their busy, dont feel like delaing with a problem or just plain out dont give two S**Ts. Thats my experiance. I've had problems and they swore it was Normal Operation, then later i have to go get new parts.

 

If they can tell you to go away for the next 20,000 miles then they won't have to replace your alternator. (Which sounds like it might have a defective voltage regulator in it)

 

Thanks for the ideas guys. I suspected the voltage regulator but I couldn't find any relationship to the fact that the engine doesn't run smooth when this happen.

I thought the alternator erratic output is due to the fact that the engine fluctuates in RPM. Again, when this happens and I accelerate I can feel my car shaking or hesitating like somebody cuts the fuel very fastly. The amplitude of this is in direct relationship with the voltage oscilation. Can a bad alternator be the cause of this engine behavior or the vice-versa? I thought maybe I have a bad spark or so.

The interesting thing is that this happens with NO reason and it can go on and off several times in a day.

It always happen right after I start then engine when the ammeter needle goes close to 17 V while shaking and then in 2-5 min it comes down to 14 or so and the shaking stops. Then, while driving it can start again all of a sudden.

Thanks for any idea that I can take up with the GM guys!