Squawking belts

I have a 2003 Mazda Protege. Last summer I had some work done on it and I had them change the belts because they were making a lot of noise. Shortly afterwards, the annoying noise came back. The noise only occurs when the engine is cold. After driving 10 minutes or so the noise goes away. A week or two ago I took my car to a shop to see if they could fix the noise but, they said everything looked fine and the belts looked new. Shortly afterwards I used some “belt conditioner” spray on hoping to get rid of the noise. Since then, the noise has only gotten louder. Is there anything I can do?

The noise may be a symptom of something besides the belts–if they are new and properly tensioned. Something the belt goes around may have a resistance that is causing the noise, and is soulds like it may be failing. Check for some pulley that is not as it should be.

I’ve always had to re-tension the belts after letting them run for a couple of days. Belt conditioner cannot replace weak tension. I’ll bet the belts loosened up a touch since they were last installed.

I agree, the reason it only squawks when the engine is first started is because that is when the battery charge is at its lowest and the alternator is putting out maximum amps to recharge the battery. After the battery is fully charged, the alternator isn’t putting out the amps anymore and becomes easier to turn. Sometimes the squawking stops when you turn off the headlights and all other accessories that draw electric power.
Belts stretch a little bit as they break in and it probably just needs to be retightend.