Daily driver, 02 LS6 ZO6. It started last night, upon acceleration it studders and stumbles, at 60mph in 6th the tach on the HUD bounces up and down a digit, and in neutral I heard a deep distinct knocking noise a few times.

Something similar happened to me in the past with a 94 LT1, the "studdering" was more abrupt but less frequent. It turned out to be a spark plug wire, and one of the cylinders wasnt firing.

I think its most likely a fouled plug or two, but Im not sure. A spun rod bearing came to mind but I think that is more audible, especially from the engine bay although Ive never heard a spun rod bearing before.

I also thought that maybe It's a bad batch of gas, but I got my 91 from the usual Chevron that I usually get from. So it wasnt like it was a no name station Ive never been to before.

I wasnt driving it hard last night, just normally shifting at 2k and treating it nicely when it happend. What is this most likely? I really can afford a bottom end right now, so if its more than a spark plug Im sorry to say that I might be trading down to maybe a 350Z.....

 

Have you scanned it?

 

find someone with autotap in your area, or something similar. check all the wires and plugs. you may even try cleaning your maf, a dirty maf can cause a lot of problems and is mostly the last thing you would check. just throwing ideas out there.

does this only do it in 6th?

 

I have a friend with a 99 SS camaro and his was breaking up like that. See if you can get to a shop or someone who knows how to use EFI Live. I don't know how to work it but it worked miracles on my buddies car. It shows you everything right off of the laptop. Not saying to shy away from the Z at all though

 

Yeah I scanned it, on the C5 if you hold down the options button and hit the fuel botton 4 times consecutively you will get a digital readout of all the OBD2 codes you would pick up on a scanner. No codes, and no check engine light.

I considered the MAF, but if the MAF was the culprit wouldnt my check engine light be on? Thanks for the replies so far.