1980 SC cold engine w/ tinny rattle

[mikesarge]

Well, I've been searching and searching, trying to find a thread with a similar noise, and a solution.

I believe my car has updated tensioners (not fail-proof, I know).

This noise goes away above idle, and as it warms up, though a similar-sounding noise does happen on decel in gear especially at higher RPM, which makes me think it could be tensioners.

Does this sound familiar? Any guesses to get me pointed the right direction?

I've owned the car since about May, but it's been in storage for a while as I haven't had a place to park it where I can work on it. It pulls hard, and otherwise sounds normal to me.

My plan, once I can actually park in my new garage and leave a car on stands for a while:
1) pull chain covers, check for tensioner failure
2) pull lower valve covers, check for broken studs/barrel nuts

any other tips or ideas of what this could be?

[Trackrash]

I'm not sure I am hearing anything from inside the motor. Just maybe something around the exhaust being loose.

You can buy a stethoscope at HF and listen inside the motor. That will help pinpoint the location of any rattle.

[rosie82sc]

I had an O2 sensor plug come slightly loose, the rattle was the same as you describe.

[gazzerr]

My car does something very similar to that. I'm pretty sure it's my heat exchangers. They are loose from being too rusty and make that noise.

I recently had a pretty significant leak into one of the heat exchangers. While the exhaust was smoking I could see that there was big leaks at the headers too.

[mikesarge]

So far, I’ve found that the heat shield on my O2 is loose, but it’s not the only thing making noise. The crossover pipe from passenger side to cat seems to be making a lot of rattling based on the stethoscope. It almost sounds like there’s a bolt inside. I’ll confirm it isn’t the heat exchangers, then take that pipe off most likely.

Thanks for the tips everyone, I’ll post an update when I get one.