After having drained the transmission fluid over the weekend, I sprayed contents in a can I realized I had in the garage that is supposed to quiet belt noise and my car really didn't need it (it was more of a preemptive move) where now after having sprayed the belts they are actually making noise. Now, the check engine light has come on. I believe I may have started some maintenance inadvertently, but the truth is I can't remember the last time I had the belts changed. Anyone have something similar happen? What could it be? Did I just expose the belts needing changing by doing this? TIA.

 

If you can't remember when they've been changed then you probably need to change them. Look at the belts for ANY cracks or melted parts. If there are any, replace the belts. Don't let it get to this:

 

The Check Engine light is unrelated. Have the computer scanned with an OBD-2 scan tool to check the error codes.

I generally don't recommend using belt dressing - you've just found out why.

Check the tension and condition of the belts. If they are in fair condition but have too much slack, adjust the tension, but do not overtighten. If the ribs are dry rotted and/or starting to crack, the belts are in need of replacement; adjusting the tension may cause a rotting belt to break.

Generally, the accessory belts should be replaced every 105,000 miles or 8 years along with the timing belt, balance shaft belt, and water pump.

I highly recommend using Mitsuboshi or Bando replacement belts. Gates and Continental belts aren't my first choice, but are generally okay. I don't recommend using Goodyear or Dayco accessory belts - they tend to stretch and squeal more than the others in my experience.

 

if they belts are in good condition, you could use some degreaser on the belts (take them off), and dont forget the pulleys, now you have gunk in the grooves

also get oem belts, the ones from autozone outright suck in comparison

 

^agree, however if the belts need to be replaced. Compare the OE belt price to a Gates belt..if the Gates belt (found many places) is in line I would consider that as an option.