Can anyone make out this sound? [Video*]

[avalonshoe]

You Tube

You Tube

There's a fast knocking?? sound upon deceleration from 3000-to-750 rpm.. Sounds like it's coming from the cams. Can't figure it out. It's actually very noticeable in person, but it's sort of muffled when picked up by the camera. Listen with some earphones.

The valve cover seals are leaking but oil levels are ok good. It does not leak much per 3000k interval.

Let me know if you can't distinguish the sound, I can try to take a better video with better sound.

[avalonshoe]

Car is about 177k miles. No changes in MPG detected while driving. I kept constant revs at 3k, 5k while in park but the engine does not vibrate. However, the car vibrates excessively while driving. I can't tell if this is the wheel vibration or stuck calipers guide pins.

The noise can only be heard while the revs decreases from 3000-750rpm. I plan to jack up the engine on fours and to put it in drive mode. It sounds like it's coming from the front cam shaft, but from inside in the cabin, it sounds like it's coming from the tranny. It's pretty difficult to isolate the sound.

I will also be changing the valve cover seals soon, i'll take a picture of the cams to see if there's any sludge. Hope that there isn't any sludge preventing oil from entering the upper valve chamber

[US Route 6]

Did you ever find the solution to your problem? It sounds pretty familiar. We were looking at a used Avalon engine the other day with a similar noise. I suspect the noise is coming from the variable valve timing cam gear, potentially caused by a bad camshaft timing oil control valve. t's a really easy part to replace, but I didn't want to invest the money in an engine we may not be purchasing.

[avalonshoe]

I still don't know what the culprit is. I removed the valve covers and it looked like this:



Looks brand new to me. The surfaces were coated quite well. I did not find any oil build up or any shearing on the camshaft gears @ (~178k miles). The car does vibrate when driving at 60-70mph, but I cannot discern whether the brakes, suspension, or engine is causing it.

[TedL]

Originally Posted by avalonshoe

I still don't know what the culprit is. I removed the valve covers and it looked like this:

Looks brand new to me. The surfaces were coated quite well. I did not find any oil build up or any shearing on the camshaft gears @ (~178k miles). The car does vibrate when driving at 60-70mph, but I cannot discern whether the brakes, suspension, or engine is causing it.

Vibration at 60-70? Wheel balance/tire problems and bad axles should be on your list too.

[BadChicken]

sounds like the noise is coming from the vvt-i gear, but its hard to tell on the video

[US Route 6]

Originally Posted by BadChicken

sounds like the noise is coming from the vvt-i gear, but its hard to tell on the video

So does that make the gear bad, or the timing oil control valve, or the actuator? Looks like those gears run around 200 bucks a piece...

[BadChicken]

just the gears

[US Route 6]

Are the gears a dealer only item? I'm guessing that they aren't servicable.

[BadChicken]

i would just go to the dealer to get them