The Protege is prone to squeal a belt, often when you turn on the AC or the AC and lights, or when it is wet. What is causing this and how to find out which belt it is? First, belt squeal is caused by a loose belt or out of alignment pullies. Loose belt is easy enough. If you tighten the belt and it still squeals, it is NOT a loose belt. First, to find out which belt is doing the squealing, you will need to run the motor, turn everything on (lights, SC, etc.) and let it squeal for as long as it will. When an alternator is under load it really pulls hard on the belt. Then go out and touch each of the belts. The squealer will be so hot you cannot touch it for more than a split second without being burned due to the friction, the other belt will likely be warm, but not hot. The AC is NOT the problem. The alternator is NOT the problem. The power steering is NOt the problem. If you replace those you are wasting money. The problem is pulley alignment and usually it is the alternator. I assume the alternator mount and design is warping over time since I did replace the alternator and pulley (it was due at 170,000 miles anyway) and I still had the squeal. The only fix that worked for me is the Goodyear Gatorback belts. They are made to prevent squeal and THEY WORK. You can go to somewhere like Rockauto and get the Gatorback cheap. If you get any other belt you will be sorry. Since the Gatorback stretches a lot (which is part of the totally weird looking design), you can tighten it more than a regular belt and when you push on it, it feels like a tight rubber band. So before you waste money on a new AC compressor, crankshaft or other pullies, or on an alternator, get a pair of Gatorbacks and install them. In almost all cases you will find the squeal has gone away. I had a Jeep and that was the ONLY thing that worked on the Jeep also. Good luck.

 

Nice job, moozmooz.
What also happens is that the alternator pulley gets polished so smooth that the belt cannot grip. Using some sandpaper to roughen the grooves in the pulley will often fix the squeal.

 

Great tip! Whenever replacing the belt it would be a good idea to sand the pulleys using some emory cloth because not only does it get polished, it gets coated with material from the belt. Probably a good idea to sand all the pulleys when you replace a belt.

 

Very helpful thread. My new to me 99 protégé squeals when accelerating past 3500 rpms and it's been driving me crazy. I will have to give these tips a try.

 

Also use a wire brush to clean the grooves in the pullies. I have seen those groves totally filled with crud. Emory cloth is about the only thing that really works for sanding and you can tear off a piece long ways that is the width of the inside of the pulley. I use 120 grit.