Belt Tensioner

The automatic drive belt tensioner can be checked as follows:
1. With the engine running, observe the drive belt tensioner movement. The drive belt tensioner should move (respond) when the A/C clutch cycles or when the engine is accelerated rapidly. If the drive belt tensioner movement is constant without A/C clutch cycling or acceleration, a pulley or shaft is probably bent or a pulley is out of round. In rare cases, excessive drive belt rideout (uneven depth of grooves in drive belt) can cause excessive drive belt tensioner movement. This condition can be checked by replacing the suspect drive belt with a known good O.E.M. drive belt and repeating the observation.