twitchee2
Member
So a little back story here. I have a 2002 SR5 with 248k on the motor. Two weekends ago I did a full trans flush (18 qt worth), flushed the brake fluid and changed the oil. Gained almost 3 mpg which was awesome.
Fast forward to this last weekend. I drove from SoCal to Reno (500 miles) saw a bunch of friends and then sunday morning we woke up to drive the same 500 miles home. Fired it up and there was a very funky sound coming from the engine bay, almost like a belt slapping or a shredded belt slapping a cover, but it would go away after ~3s. The motor ran as good as ever so I ran it. Drove it all the way home. On Monday it started getting worse so I parked it and grabbed my sisters 4th gen that I've been driving all week.
Started looking into it to try and find the problem. I had 3 theories.
1. My AC pump has been making noises but it was blowing cold and still is blowing cold, so that is out
2. When I did my timing belt I did not change the Tensioner, maybe that is bad. Still possibly bad.
3. Spun Rod bearing. Not likely because it came on so quick. Still need to pull the oil filter and cut it open to check. I think this is not very likely, the motor doesn't knock.
Things I have checked:
1. Pulled AC and PS belts - no change.
2. Pulled Timing cover - Nothing obviously loose, hard to see much.
3. Pulled valve cover - Again nothing obvious and looks normal.
4. Pulled Timing cover again and held it out of the way of the fan and belts, ran for about 2 minutes. Sounds GONE. Put the cover back on and cannot reproduce the sound. At this point it was dark and late. I went home. Fast forward to today, I found a bolt sitting on top of my Trans cooler lines directly below the crank pulley.
New theory - I think there was a bold loose that was flopping around in my timing cover area and it flew out while I was running with the cover over.
So I need your help guys. Where does this bolt go? Pictures and video below.


Video: https://www.youtube.com/watch?v=YtoeGAUDy4c
Edit:
So I found it. Good call on the plate behind the pulley.

If you look real close, the other bolt is pretty banged up. I bet the bolt was just flopping around in the pulley. I think once I shut it down, the bolt would settle at the bottom of the cam pulley. Then once i started the engine, the bolt would bounce around until the rpms got up high enough for it to be centrifugally forced to the outside of the pulley and then was quiet. The other bolt got knocked around on start up.
At least it is mostly a non-issue. I will grab a new bolt and slap it in. I think i am going to take the others out and put some lock-tite on them as well.
Thanks for all the help!
Fast forward to this last weekend. I drove from SoCal to Reno (500 miles) saw a bunch of friends and then sunday morning we woke up to drive the same 500 miles home. Fired it up and there was a very funky sound coming from the engine bay, almost like a belt slapping or a shredded belt slapping a cover, but it would go away after ~3s. The motor ran as good as ever so I ran it. Drove it all the way home. On Monday it started getting worse so I parked it and grabbed my sisters 4th gen that I've been driving all week.
Started looking into it to try and find the problem. I had 3 theories.
1. My AC pump has been making noises but it was blowing cold and still is blowing cold, so that is out
2. When I did my timing belt I did not change the Tensioner, maybe that is bad. Still possibly bad.
3. Spun Rod bearing. Not likely because it came on so quick. Still need to pull the oil filter and cut it open to check. I think this is not very likely, the motor doesn't knock.
Things I have checked:
1. Pulled AC and PS belts - no change.
2. Pulled Timing cover - Nothing obviously loose, hard to see much.
3. Pulled valve cover - Again nothing obvious and looks normal.
4. Pulled Timing cover again and held it out of the way of the fan and belts, ran for about 2 minutes. Sounds GONE. Put the cover back on and cannot reproduce the sound. At this point it was dark and late. I went home. Fast forward to today, I found a bolt sitting on top of my Trans cooler lines directly below the crank pulley.
New theory - I think there was a bold loose that was flopping around in my timing cover area and it flew out while I was running with the cover over.
So I need your help guys. Where does this bolt go? Pictures and video below.


Video: https://www.youtube.com/watch?v=YtoeGAUDy4c
Edit:
So I found it. Good call on the plate behind the pulley.

If you look real close, the other bolt is pretty banged up. I bet the bolt was just flopping around in the pulley. I think once I shut it down, the bolt would settle at the bottom of the cam pulley. Then once i started the engine, the bolt would bounce around until the rpms got up high enough for it to be centrifugally forced to the outside of the pulley and then was quiet. The other bolt got knocked around on start up.
At least it is mostly a non-issue. I will grab a new bolt and slap it in. I think i am going to take the others out and put some lock-tite on them as well.
Thanks for all the help!
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