bucking and jerking is back

[Mikebox]

Yes, they pulley itself (grooved pulley that the serpentine belt travels on should always be turning when engine is running. When A/C compressor is off the clutch (center part of pulley facing the right hand side of car should be stationary) When a/c compressor engages, that part should be spinning with the pulley as well.

I cant believe the pulley is not spinning and the belt hasn't self destructed yet. This usually happens within a few minutes of siezed pulley.

As for the CEL light, depends on whether it was a hard or soft code. Soft codes will drop after a number of driving cycles. Hard codes have to be reset with a scan tool

[Stan the Man]

Originally Posted by Mikebox

Yes, they pulley itself (grooved pulley that the serpentine belt travels on should always be turning when engine is running. When A/C compressor is off the clutch (center part of pulley facing the right hand side of car should be stationary) When a/c compressor engages, that part should be spinning with the pulley as well.

I cant believe the pulley is not spinning and the belt hasn't self destructed yet. This usually happens within a few minutes of siezed pulley.

As for the CEL light, depends on whether it was a hard or soft code. Soft codes will drop after a number of driving cycles. Hard codes have to be reset with a scan tool

Thanks for the advice. I'll double-check, but I'm positive that the pulley isn't turning at all. So running it at all could snap the belt, whether the A/C or defroster is on or not, right? If it is indeed seized, it's been running for 3 weeks or so now.

Could this pulley not turning put stress on the other pulley bearings, like the water pump pulley or idler pulley? Because that's where it sounds like the screeching is coming form.

Sounds like I might need some A/C work. Does this sound like a problem with the compressor, or just the clutch? Or can they even be replaced separately?

Also, is there a way to know if my CEL code is a hard one or soft one? I'm going to call the repair shop back & see if they still have the codes from last week.

[SRamsey625]

Correct. The outside of the pulley will always turn. The inside (clutch) will turn and stop as the clutch engages and disengages respectively. If you have another vehicle, watch the compressor with the a/c or defrost on. You will see what I mean.
If your compressor is bad, it wont matter whether you run defrost or not. I wouldn't since it's not functioning anyway. If you have AAA or something, I would recommend having it towed. Try not to drive it if you can avoid it, if that is indeed the problem. Like I said, all your critical systems i.e. cooling, charging, P/S all depend on this one belt. If it breaks, you lose it all. Your mechanic can also read the code that is up. It may be something entrirely different. He can also reset it to turn the CEL off.
You could try to tackle the job yourself but it is somewhat labor intensive and is under pressure.

[Dngrsone]

Yes, the AC pulley should always be turning. Likely the clutch has siezed but possibly also the pump.

If you want to put off replacing the compressor/clutch assy (I don't recommend it... now's the time when AC maintenance will be cheap), then go down to the Auto parts store and buy a new serpentine belt, telling the sales rep that you DO NOT have an AC. There are a couple sizes and corresponding paths for the serpentine depending on whether you have an AC installed or not. You will want to replace that belt either way.

[wiswind]

To turn the CEL off yourself....
Remove the Negative Battery cable...
Leave it disconnected for about 5 minutes or so.....reconnection right away may not clear the CEL.
Reconnect.....
This will cause the CEL to be off.....
If the CEL comes back on......(and you have left the negative cable off long enough) you still have a contition causing the light to come on.

NOTE: Removing the Negative battery cable will also clear out your preset radio stations and your "drivability" information in the computer.
The computer WILL "Re-learn" this information.
You may notice that your transmission sift points may be slightly different until the computer relearns all the data. The relearn process is pretty quick...and not a big deal.....

I looked at my air conditioning pulley today......
I did it with the engine off.....and the drive belt off......The "outer" part of the pulley turns very easily....and the center part (the main body of the pulley) does not turn.

If you look at the pulley (use a flashlight) with the engine running (be very careful to not get yourself into the belt)....You should see the metal "lip" on each side of the belt.....the part that keeps the belt from sliding off the pulley......This metal that you can just barely see on each side of the belt....SHOULD BE TURNING. The part of the pulley that you can see from looking from the side......will not be turning......THIS IS NORMAL.

Just the small surface that is at the belt surface turns.....it is a ring.

[Stan the Man]

I double-checked, and that sucker isn't turning at all on the outside. If that's what has bene causing the screeching, it's lasted for over 3 weeks, and the belt seems to be all right. The belt just slides over the grooves on the outside of the A/C pulley. I haven't let my wife drive it at all since I began to suspect the water pump might have been the problem.

The mechanic shop is just around the corner, so I feel OK driving it there, but not any further. Thanks a million for the tip about getting a belt that doesn't route through the A/C. If the repair is too much, I might do that. But I agree with you - now is probably the best time to have that fixed.

I expect I'll probably have to get either a new water pump or idler pulley. I think that the extra friction caused by the A/C pulley not turning has over-stressed one of those two bearings, causing the screeching sound. What do you guys think?

UPDATE: OH MY GOD!! I just called the auto parts store for availability on the compressor/clutch assembly, and just for the clutch. $254 for a reconditioned compressor/clutch unit ($344 new,) plus about $164 for the new filter dryer & another warranty-required part. The clutch by itself is $102. Man, I hope it's just the clutch!

[LeSabre97mint]

Stan

The "Pulley" on the air conditioner will turn all of the time. The "air conditioner pump" will only turn when the clutch on the pump is engaged.

Start up your engine and look at the pulley on the airconditioner pump. If you see smoke coming from the pulley the bearing is locked up and so is the pump. If no smoke your noise may be coming from another area.

I'd pull the belt and check all of the pulleys. It's the only way you'll find the problem.

Regards

Dan

[12Ounce]

I doubt that there will be harm done to the other pulleys if the ac is locked up. In the scheme of engine belt things, the crankshaft pulley supplys the power (force x velocity) ...every other pulley is a power "load". The ac compressor is significantly the largest load of all so it is placed "first" on the belt after the crank pulley ... then comes the alternator, power strng, etc. Idler pulleys are inserted as necessary to increase the "wrap" of the belt around particular pulleys. As it travels over each load pulley, the belt loses a bit of its tension (force)... when the belt gets back to the crankshaft pulley, almost all the tension is gone... an ideal location for the spring loaded tensioner, if there are no other considerations.

So a locked-up ac pulley will cause increased belt forces on the ac pulley and the crank pulley ... little increase on anything else.

[Mikebox]

I wouldn't worry about the other pulleys either unless by feel they have play, resistance, wobble or squeals, then replace as necessary. As for the A/c compressor, it is relatively easy to replace yourself but you need to have a qualified tech, remove the refrigerant first. If you do replace, do replace the accumulator too as it is the only thing that dries the system. Make sure you measure any oil that pours out of the two parts as you will need to replace that much in the system when you install new parts. Check that your lines do not have a black film in them; if they do you will have to have the lines, evap and condensor flushed out before you can proceed.
Replace the compressor, accumulator and then take to shop (if you dont have access to an a/c vacuum pump) vacuum the system down as close to 29" Hg as possible and run vac for 45minutes. The system is now ready to recharge with r134.

[Stan the Man]

Haven't posted back to let everyone know how it all turned out.

The problem was the cam sensor. There was a semi-circular piece that spins inside the housing that was bent. It was tearing the heck out of the plastic inside the housing as it spun.

It was covered under the extended warranty I got, except for the $100 deductible. But the screeching is gone, it doesn't stall out, and the CEL has stayed off for several day snow.

I'm glad it's fixed, and I appreciate everyone's help here.