I washed my engine bay to clean off some battery acid and some dirt and the next day I noticed ticking noises. At idle, it ticks constant but as the rpms speed up, so does the ticking noise. I've tried WD40 and/or belt dressing on the belt and accessories and nothing. So much in fact that the belt started slipping. I'm assuming it's due to the water and engine cleaner on moving parts so i've sprayed lubricant everywhere and nothing. Anything else I missed???

 

Maybe it's one of the accessories themselves? (alternator, A/C?) On an older car, I'd just start removing belts and running the engine without certain accessories to pinpoint it.

I think our car has a serpentine belt, (I've never looked), so that may be tougher to do...

 

First thing I'd do is to put a wrench on the auto tensioner and flex it back and forth a few times. Then start the engine and check the noise.

If it's still there, I'd remove the serpentine belt and then start it again. If the sound is gone, it's likely the AT.

 

For future reference, a detailer once told me that if you're going to be washing the engine bay with a hose or any type of water spray, to do it with the engine running. This way you can hear if you're screwing anything up (sputtering, idle changing etc).