2002 SS M6

My hope is this is just a battery issue but thought I'd check here first for some input.

I noticed this as it got cold outside, never noticed this problem during the summer. Going off the DASH GAUGE if I'm cruising along and push in the clutch (coming off the highway offramp or something) and coast, my volt reading drops to around 8, the lights dim, etc and then bounces back up to around 15.

When I first start the car up the volt reading is over 16 almost 17 probably and bounces a little lower then back up...oscillating between probably 16 and 16.5 or 17. The headlights and the dash lights all glow brighter then slightly dimmer as this happens. After the car warms up and the idle comes back down this goes away completely and the car settles in around 15 or so.

When I put the car in gear and drive, I get the oscillating problem again but the reading is slightly less than when the car was cold cold on startup, more like 15.5 up to 16, just a little lower than the high red warning.

In other words, car in gear and it's cold outside (less than 45) and I notice the problem and the lights flicker so I can only wonder what other drivers think. When it was warmer over the summer and fall I didn't notice this at all.

I've had the car 2 years, same battery as when I bought it and there wasn't a readily seen sticker on it with a date.

Was planning on taking the battery in but just haven't had the time and don't want to damage the electrical system in any way so the cars been parked. I'll start there but didn't know if this was a telltale sign of something different.

thanks!
John

 

Yeah, I would have the battery load tested first. I've had the erratic charging/ flickering lights syndrome before, and it was one bad cell in the battery. If not that, then have the alternator tested next. It could have a bad voltage regulator.

 

Just ran over to the auto store and they tested the battery, said it was fine but had a low charge. And from the readings on that they don't think it's the alternator either (they tested it in the car, car on/off, etc). Said probably a loose pulley or something else but thought the battery and alternator were fine.

 

Check your battery, junction, and ground connections to make sure they're clean, not green.

 

The terminals are fine and the cables are tight. I pulled them off and there was no corrosion or anything, they were fine. Hooked 'em back up and no difference in the way the car runs.

How tight is the tension pulley supposed to be? I'm able to grab it and roll my wrist and move it, or grab the belt and pull on it and the pulley will move easily. With the car running, if I rev it just to something over 1000 RPM you can see that pulley move and this is when the lights and volt meter flicker.

If that sounds normal I'll pull the alternator and get that tested when I have some time or just drop it off at a shop and have them fix it. Otherwise if that pulley is supposed to be tighter I'll replace that and see what happens.

thanks!

 

You shouldn't be able to "free wheel" any of the pulleys. It should take a breaker bar, or a wrench with a bit of mule power to back off the tensioner enough to lessen the belt tension on any given pulley. If your tensioner moves away easily by hand, it's shot.

 

I'll get that replaced tonight then, thanks!
I thought that seemed wrong when I was able to push on it and move it like that...to the point I could have pulled the belt off with my other hand.