My 4runner just started this a few days ago.
Its a background hum from near the center of the engine best I can tell though I don't have proper tool to narrow down more.
It drives and shifts fine, currently has a bad IAC (probably not related though dunno) and runs fine just with this loud hum at most times at idle and revving at idle or on the road driving until at speed it kind of fades out with the extra wind noise, etc.
I made a short vid but don't have youtube acct or others to link to here currently.
I tried to rule out as much as I could including the power steering, had the wife move the wheel back and forth since I was checking my steering for play anyways and didn't get worse or better. It was quiet for a bit then turned on headlights and heater full blast and it got worse again and stayed that way even after turning off lights and heater fan so not sure if its even load related. Got louder as I blipped the throttle and then of course quiets down. No valve or cylinder noise and engine runs good.
Started thinking water pump, air intake seal somewhere, alternator. Fan clutch is tight. I'll have to get a video up somehow soon. any ideas would be thanked
EDIT: I think it might likely be a bad tensioner pulley or other pulley. all my belts are brand new and noise didn't start til a few days ago. Will report back later
Its a background hum from near the center of the engine best I can tell though I don't have proper tool to narrow down more.
It drives and shifts fine, currently has a bad IAC (probably not related though dunno) and runs fine just with this loud hum at most times at idle and revving at idle or on the road driving until at speed it kind of fades out with the extra wind noise, etc.
I made a short vid but don't have youtube acct or others to link to here currently.
I tried to rule out as much as I could including the power steering, had the wife move the wheel back and forth since I was checking my steering for play anyways and didn't get worse or better. It was quiet for a bit then turned on headlights and heater full blast and it got worse again and stayed that way even after turning off lights and heater fan so not sure if its even load related. Got louder as I blipped the throttle and then of course quiets down. No valve or cylinder noise and engine runs good.
Started thinking water pump, air intake seal somewhere, alternator. Fan clutch is tight. I'll have to get a video up somehow soon. any ideas would be thanked
EDIT: I think it might likely be a bad tensioner pulley or other pulley. all my belts are brand new and noise didn't start til a few days ago. Will report back later
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