blkZ28spt

My engine started knocking a little over a week ago, seems to be centered around the back of the passenger side. At first I thought it was exhaust banging as the engine shakes quite a bit at idle, but consensus was that it was indeed knock an exhaust bang was just wishfull thinking on my part. It's not very bad and is fairly inconsistent. It still drives perfecty fine, though occassionally it shifts up early and refuses to downshift or unlock the converter, as if in limp home mode, but it's done that once in a great while before.

I have an engine light for a TPS code, but the code has been there for months. I've had it since I swapped to a ported throttle body that was originally on a newer car with a differently sized throttle body 'cam'. I had a few people listen to it at our callout show awhile ago and got all kinds of different possibilities, everything from a bearing to out, some TPS problem leading to not enough fuel injected at idle, injector crapping out, loose rocker, lifter collapsing...

I've been busy with classes and havn't tried to try and diagnose it, and don't foresee having much time to.

What is the chance I'd find anything out by pulling the valvecover and checking the oil filter for metal? I might be able to do that on Friday.....

Thanks in advance for any help on what is a somewhat common question, I am sure.

gwj

Are you getting any other codes? Have you had a scanner hooked up while running and checked KR, timing,misfires, etc?
Your engine knock could be a serious problem or could be something fairly simple. A loud audible knock or rattle at idle whether constant or occasionally is not a good sign.
I'm ignoring any TPS codes as that sounds like a different issue.

blkZ28spt

No scanner has been hooked up, nor do I have access to one. I have the code pulled about once a month to make sure the TPS code is indeed the only one. I keep forgetting or going by when it's closed but I will triple check for more codes tomorrow. (went just before this started and it was only the one)

It's a fairly loud, audible knock. Sometimes I hear it while I'm sitting in the car with the windows down, whehter it be echoing off something next to me or just plain loud enough to hear (over my exhaust at that). It doens't always do it constantly. It was almost cyclic in nature at times, going with the rythm of the engine with it's very slight stall/surge at idle.


Paraphrased: It does not audibly knock for every revolution of the motor. Sometimes it is louder than others.