Symptom: Loud rattling noise at idle - didn't happen slowly over time; rather, it happened suddenly (on mine anyway).

The other day I went to start the '92 SSE supercharged and I heard a rattling noise for a second when the starter motor disengaged. I drove the car home and noticed that there was a now loud rattling noise at idle, but it went away when throttle was applied. My first thought was maybe a broken tooth on the crank or the starter motor, but this wouldn't explain the rattling noise at idle, just the noise while starting.

I listened using a piece of rubber hose, and the noise sounded like it was coming from the harmonic balancer pulley area, or maybe the timing chain/gears behind it, so I removed the 2 accessory belts, one-at-a-time, and ran the engine for just a few seconds, and when both belts were off the noise was gone, so I knew it wasn't the water pump, AC pump, PS pump, or any of the other pulleys.

I used a small mirror to look at the side of the balancer pulley, and I could see that the rubber was cracked and separated on the outside edge where it meets the pulley itself. I also noticed that there were now small pieces of crumbled rubber on the ground under the engine, so this confirmed my suspicion that the rubber on the balancer was shot.

I called a few local dealers. As I called more than one dealer, I learned that one of them gave me the wrong balancer part #, but the other 2 gave me a different (correct) part number and one of them had it in stock. I was surprised to learn that the balancer for the '92 supercharged engine is a different part number than for the '93 and '94. I thought the '92/'93 engines were the same and the '94/''95 engines were the same?

Anyway, I bought the part from the dealer who had it in stock, and paid a local independent shop to install it. It took them less than 1 hour, and they charged $70 for the labor. The dealer wanted $229 for labor, and another local independent shop wanted $200 for labor, so shop around. I would have replaced it myself, but it happened at a bad time :(, and $70 seems very reasonable to me.

There are more and more differences between the 92 and 93 coming to light. Not just the valvetrain (rockers/heads). How much was the balancer?

I had this same thing happen to my 1998 GP SE. I did it myself, but got the part from a club Gp member. Cost for the part was $40 bucks including shipment. Took two days to do as I didn't have a impact wrench. I used my cheater barr that I call Saddam- because it'* the mother of all cheater bars.

The cost at the dealer was $155.
gmpartsdirect has the part for less than $100 but I didn't have the option of waiting for it to be shipped to me.

$200 for labour????!!! I have had to take mine off twice now (once for replacing it and once to change the crank sensor). The whole job maybe took 45 minutes total. The thing that took the most time was searching the shop for bolts that would be long enough to work in the puller. I used a 2 inch 3/8 extension in the main bolt hole so as not to wrench the threads with the puller and then used the impact...easy as pie (when you have the right tools). I couldn't imagine pulling it off with a pry bar ughhh