So I was driving today when the PS went out. I pulled over to see my belt was off but in one piece. Now I'm getting towed home as we speak. What could have caused this. The belt is about a year old.

 

My guesses would be:
- A pulley seized (but normally this would damage the belt as well and cause a lot of belt noise).
- A pulley is no longer aligned properly, cocking at an angle and let the belt walk off.
- The spring for the tensioner is weak and failed.

 

My first bet is going to be the tensioner. Common failure part in gm cars. Or in my experience with them atleast. Its easy to check.

 

The tensioner is the one that makes the most sense to me. I have dealt with one where the pulley itself had a bearing problem (just made noise) and I know someone that had to get the entire tensioner assembly changed.

Outside of that, with all the GMs I've messed with, I haven't seen any others fail. But I agree, easy to check and would seem like the most likely culprit.

 

I would Also check the coolant elbows, power steering pump/hose and water pump for leaks. If enough of any of those liquids get onto a pully or the belt it will cause the belt to slip or come off.
I feel the same as Jason. My first thought would be the tensoiner. But if it's good, I would Check these other things.

 

They fail on every saturn iv seen in my life time haha. Spring just gives up the ghost, sorta drove home on battery power one time haha, then had to replace the battery the next week, and power stearing pumo after that thoes things were a bitch to work on.... that's why I bought my monte... but I digress.

Also seen it on enough other gm cars to make a mental note.

 

X4 on the tensioner

 

Only the 3800's had coolant elbows. The 3.4 engines did not. But checking for traces of coolant or anything that could lube up a pulley is a good thought.

My thoughts are still on the tensioner failing.

 

Thanks Jason. I didn't know that. I've had the 2.8, 3.1 and now the 3.8. Guess I need to do some reading on the 3.4!

 

Didn't expect to see so many responses. Ty i will wait till tomorrow to check her over since i am having plumbing issues at the house today as well. I probaly should note that I've been dealing with what I believe to be a huge vac leak. The car has been doing the high idle until its warm and even then she rides rough as hell. So this is probaly what lead me here in the first place.