I recently noticed a strange noise on my '92 SSE */c. The engine sounds noisier than usual at idle. The noise sounds like it'* coming from the nose of the supercharger; all other pulleys sound quiet. There'* also a noise during acceleration in 1st and 2nd gear. The upper belt tensioner jumps a bit while the engine is running, too. Just for kicks, I replaced the almost new pulley on that tensioner with another new one, but it made no difference. I also swapped the upper tensioner from my '93 onto the '92, and it jumped also, but neither tensioner jumps when mounted on my '93.

Because I thought the noise was coming from the supercharger nose, I replaced the supercharger with one that I rebuilt the nose on (new bearings, coupler, oil seal, and oil) and to my amazement, the noise is still present and it still sounds like it'* coming from the supercharger nose.

Is it possible that something else is making it sound like the noise is coming from the supercharger nose when it really isn't?

I've recently replaced the harmonic balancer, alternator, all idler and tensoner pulleys (but not the tensioner spring assemblies), power steering pump, and as I said, the supercharger.

I haven't replaced the water pump, ac compressor, or belt tensioner spring assemblies (but as I said, all tensioner pulleys were replaced).

Any wild ideas? Could a belt tensioner spring mechanism cause a noise that sounds like it'* coming from somewhere else? Water Pump? Could it be a problem in the engine?

Thanks!

I'd go straight to the belt tensioner personally.. You've replaced everything else and you shouldn't have any "jumping"

Agreed.

Another option is that you have the incorrect belt on, causing the tensioner to bottom out. Check it out and make sure it'* the correct length.

Wow, I have that similar problem, Hey bill would a worn belt make the engine run rough?, I did change all the sensors on my car and still to no vail it seems to run rough at idle with the belt tensioner making a rattle, (Brand new Belt tensioner too)

The belt is the right size, and it'* only about 6 months old. The mark on the side of the tensioner is within the marked limits and isn't near either side marker.

I doubt it'* the belt tensioner spring because I just swapped the tensioner with the one from my '93, and it'* still jumping around a bit sporadically.

uhmm, I wonder now if maybe some vacumm leaks are occurring, because I have replaced every sensor on the car brand new and not remans. cant seem to find any leaks but if there is a better way in finding a vacumm leaks please let me know. - NO Codes on the scanner nor SES light on. - uhmm?

[quote="bigbadbonneville"]Nope, no SES light or error codes, and it always starts easily, runs strong, gets decent gas mileage, and has never stalled. I've hunted for vacuum leaks on multiple occasions and I've replaced some of the vacuum fittings and hoses for good measure, but I've never found anything that appeared to be leaking, and the last time I hunted for a leak, I used a vacuum gun.

Sounds like the infamous and never popular harmonic balancer. Take the belts off and try turning it. If it moves at all without turning the engine its your problem. Brace yourself for the price of a replacement one.

I thought my coupler was going, it was the water pump. Go figure

Bill...pull the tension off the belts and check all the pulleys and wp etc. Anything feel odd?