Hey guys,
I've been chasing down a new noise on the 01 4Runner the last few months.
This is not my daily driver so I have been slowly tinkering with it.
The vehicle has 196kish miles and I did the timing belt, water pump and all the associated parts with this OEM kit (screenshot attached) about 2 years and 8k miles ago.
The noise started a few months and 500ish miles ago.
I went ahead and replaced the original factory alternator and AC Idler pulley as i thought it could be the source of the sound.
(Bought factory toyota parts from the dealer)
At this point, I ran the vehicle today without any aux belts or fan mount attached and the sound is still present.
I have tried tracking it down with a mechanic stethoscope and a big solid steel rod and it seems the loudest on the tensioner roller and the timing idler roller between the two cam pulleys.
It is definitely a lot louder with the timing cover off and really seems to be on the front of the engine and not valve train related but I could be wrong.
I did check valve clearances when I replaced the VC gaskets a few years back and everything was within spec.
I have not taken the Crank pulley/Harmonic balancer off yet, but did pull out the TB tensioner and partially moved the belt to see if I could find any play in the tensioner roller, idler roller and water pump. All of them seem to spin freely and quietly. The TB tensioner roller, has a slight front to back play but I cant tell if its bearing related or simply because its on that hinged mount to allow the tensioner to work.
(I'll know more when I get some long enough bolts to pull the crank pulley and last timing cover off.)
The reason Im posting these videos and reaching out for your help is because im concerned Ill get it all apart and still not know the source of the noise.
Posting a link to a shared folder that has several videos, if you have time to check some out and lend some advice; it is greatly appreciated!
All belts and covers, fully assembled (March 2024)-
Timing Cover off (June 2024)-
Timing cover, aux belts, fan mount, etc. removed ( 4Runner Noise 4 June 2024)-
Google Drive Folder of 4Runner Noise Videos
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Learning to wrench on my first 4Runner
2001 2WD Limited Purchased 05/2020 with 188k miles