I was on the highway yesterday and put my foot down to merge and all the sudden batt light came on, powr steering was gone and A/C light was blinking. I knew the belt was the prob but I didn't know exactly what happened. turns out it just popped off and was sittin in there. well now it keeps doing it...first only when id accel hard, but now even when i start it the stupid thing pops off. is this more likely to be a stretched belt or bad tensioner? thanks!

 

When was the last time you had that belt replaced? I'm thinking tensioner, but it could be either.

 

got the car used a few weeks ago...belt doesn't look cracked.

 

im gonna say maybe ur tensioner pulley is bent so the belt slides off at higher rpms.

 

yup. check the pulley or the tensioner. make sure its not loose and the tensioner bolt is centered. sounds simple but people overlook the obvious.

 

check your harmonic balancer (your main large crank pulley) These pulleys get old and the rubber within the pulley can begin to separate causing all kinds of problems. (Run a straight line of white marker from the pulley bolt to the outer edge of pulley, run engine awhile and see if the line is no longer straight, if so the,bad harmonic balancer (main pulley). Also, when the belt tensioner starts going south it will throw serpentine belts as well. BTW, throwing a serpentine belt will stop your water pump from working....which will cause your car to overheat VERY QUICKLY!!!!! which could lead to a BLOWN HEADGASKET!!$$$$...not good....

 

oh yea I completely forgot about the water pump! thanks for the reminder. It happened the first time on the highway...I drove it to safety (10 minutes maybe and not very hard. Since then I haven't driven it 10 feet w/out the belt. I tried a new belt and that didnt help...new belt tensioner assembly is on its way!

thanks for the replies