One problem related to engine belts and pulleys has been reported for the 2003 Mitsubishi Montero Sport. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Mitsubishi Montero Sport based on all problems reported for the 2003 Montero Sport.
Pin in the harmonic balancer broke causing vehicle to sling a/c belt and drive belt causing harmonic balancer to seize up. Pin was replaced. Months later the check engine light began to come on showing a code of misfire. As well as harmonic balancer coming loose. **5/5/* belts come off on high way doing about 70 mph. Harmonic balancer loose again. Crank bolt stuck and un removable. Belts came off and got caught in fan.