Hey all,
I’m hoping a car vet can help identify a noise I’m hearing in my car.
INSIDE the cabin (not at all outside) I’m hearing a whirring noise that is related to the revs of the engine. Imagine a pulley that is loose and you can hear it wobbling slightly off it’s axis. Except this is in the car.
I’m certainly no car rookie so I’ve ruled out things like the alternator, or anything on the accessory belt (the noise can’t be heard outside the cabin anyways). It’s definitely not anything heater related.
My only guess is that I’m possibly hearing a synchro from the manual transmission? That’s a WAG, but other than that I’m stumped.
2001 Toyota Solara V6, 5 speed.
Thanks so much for the help!
Clutch throwout bearing? More sound when clutch pedal depressed or clutch in? Feel anything through the clutch pedal? Is noise present all the time - maybe just when AC compressor/clutch kicks in - though that would be noticeable when investigating the engine compartment? Present while driving or sitting still or both?
Nah, clutch in or out has no effect. Neither does being in or out of gear, other than changing the revs… sound “goes away” around 25-3000 rpms, but I’m sure it’s just drowned out by the normal cruising noises.
This is all with the A/C off… good thought I’ll turn the A/C on and see if there is a change (other than rpms).
It’s very distinct. If it wasn’t related to the rpms, I would have guessed the cabin fan or similar.
Still stumped! 
If it was more of a bubbling sound, it could be air in the cooling system especially the heater core.
Another WAG might be a bad motor/transmission mount sending vibration into the interior of the car.
Have you checked the exhaust system especially the heat shield above the catalytic converter? It might be loose and vibrating.
Does the sound go away ever? Is it cold there? When was the last time you put new oil in the trans? Could it be electrical noise coming from the speakers? Maybe had an amp put in recently?
No, the sound doesn’t go away. It’s been awhile since the tranny has been oiled or flushed, so that might be the next thing I can check. It’s nothing electrical that I can tell.