It's a 1993 toyota 4runner 3.0 . doesn't sound like a belt squeal and is every so often... any ideas?

 

i had a chirping sound once, it turned out to be the fan bracket bearing going out

 

I had the same issue. It was my blower motor.

This is really for future people looking for answers to a chirping/whistling sound.

For me, it was intermittent. When it did happen, it literally sounded like a cricket, but non-stop.

Mine only came about when the vehicle was moving. I could sit and rev the engine and it never made the sound. It seemed to be exacerbated when I accelerated, and stopped somewhat when braking, but not always. The sound didn't get faster or slower depending vehicle speed at all.

After reading through a ton of threads, it seemed the blower motor might be the culprit. I was able to finally positively confirm it by simply turning the fan completely off every time the sound happened. When I did that, the sounds ceased immediately and completely. I did this a bunch of times to make sure it wasn't a coincidence.

It's a pretty easy repair, and not too expensive.

 

I had a weird chirp intermittent while running with the clutch out, ended up being my throw out bearing……I never noticed it until my truck was running and I got out of my truck, it was a very odd chirping noise for sure….