two problems, possibly related?

well i got a '93 sl2 with a DOHC engiine.

just bought it a while ago with 128k miles, and lately it's been running a little rough.

first problem is at idle the engine vibrates pretty bad. like shaking the car enuf to knock a drink off your dash :P. anyway i've read that this could be the coolant temp. sensor, and I have a TSB article saying it could be the engine mounts. anything else it could possibly be? The engine only vibrates at idle, smooth during acceleration and coasting. It doesn't vibrate during Park/neutral, only during anythign actually moving the car, reverse, drive, etc...

second problem, when my car is stopped after a cold start, if i change gears, or stay in park and do something like turning on the A/C, a pretty noticeable squeal comes from near the a/c compressor by the drive belt. I thought this was just the drive belt and replaced it, but the squeal is still there. Is it possible this just means i need a new tensioner?

well ok thx guys, hope i can fix these ^_^.

i should also add that the car starts fine, just went it starts for about 20 seconds or so it idles at 2000 rpm. so if i shift during this time it jolts the car. usually i just wait until it dies down, but i don't consider this normal.

hope this helps someone determine the problem :)

ECTS and EGR are common causes of wacky idles, replace the ECTS with one of the new all-brass designs, and clean out or replace the EGR.

a new tensioner is a possiblity, but i've never delt with one myself.

the ECTS or EGR may also cause the vibration, but more likely, its bad mounts, lots of times you can just look at the top mount and see if its bad. if its that bad i would go ahead and replace all four

well if it's not the tensioner, could it be anything else?

i think most likely the tensioner, but maybe one of the belt driven acceserys, very small possiblity of to much crankshaft endplay. if it was endplay, you could see the crank pulley wobbling.

take to a tech to be sure, not something you can really diagiose without being there

I own a 92 SL2, I had the exact same problem as far as the serpintine belt goes, this belt drives everything air,waterpump,power steering,Alternator..After I replaced the belt I noticed the squelling noise after turning on the AC and found that I had to replace the Tensioner Pulley.

hmm ok thx for the feedback

Replace the upper motor mount, for the vibration. Saturn redid that motor mount. They will also give you new studs that are longer. You won't need new nuts. A million times better. Tensioner pulley is a definate possibility. Pretty easy to change, top bolt is a pain in the butt. but easy anyway. Just take off the tire and the splash shield on the passenger side. it will be right there.