A guy on the w-body forum also suspected an exhaust tick.

A chain flopping around would have to be hitting something in order to create that kind of noise, and I imagine I'd have more serious issues than just an idle vibration. Then again, I've never removed it so I couldn't say for sure. Part of me just doesn't want to have to deal with removing all of the accessories, draining the coolant, pulling the harmonic balancer, and replacing the timing cover gasket. It sounds like a bit of a PITA. Here'* something I found:

http://i26.photobucket.com/albums/c1...996_L36_25.jpg

You'll notice in the above picture that the timing chain doesn't have a whole lot of slack, so even if the tensioner is a tad bit loose, the chain would have to be hitting **something**.

But I'll have a listen tomorrow just to be sure, since its getting late to be revving my engine.

The timing cover has never come off. The heads have 85k miles on them, and the rest of the engine has almost 215k miles on it. I can reproduce the sound pretty easily as well. Just rev the engine. The sound from the video is a fairly accurate description of what it really sounds like in person.

The job to replace the timing set (sprockets, chain, and tensioner) would only cost me $50 + shipping, but it just looks like a really annoying job to have to do. Then again, if that'* what'* wrong, I'll have to suck it up and just do it.

Here'* video I found of a car with a loose timing chain

http://www.youtube.com/watch?v=ev5lx...eature=related

Its a different engine, sure, but its also a completely different sound.

All the timing chain stuff I found on Youtube was OHC, in one form or another. I don't know if that is a factor, but I am trying to find a pushrod motor with timing chain noise.

Don't bother. I drove out to the nearest high school parking lot, and revved my engine there for 15 minutes. I put my head as close as I could to the passenger side and the noise only got quieter. Its not the timing chain.

However, it did get louder as I put my head closer to the front exhaust manifold area. Furthermore, the engine is unusually loud from inside the car. I'm going to replace that flex pipe and go from there. Is there a chance that a bad spark plug or wire is arcing and causing that noise?

read this post then you can make a definitive judgement on valve train.


https://www.gmforum.com/2000-2005-90/2000-ssei-tick-288219/

sorry last post of page

None of those symptoms or scenarios describe my problem. I guess it must not be the valvetrain.

I think you should try Dans advice. If the wrap quiets down the noise than you've found your noise.

Check for exhaust leaks on the manifolds as well. A leak or cracked manifold can make that kind of noise.

I'll seafoam the car this weekend. If there'* an exhaust leak big enough to cause that noise, I should be able to see some smoke coming out of it.