91 corvette 6 speed, no major modifications.

2 days ago when I started the car, I could hear a misfire occasionally. Instead of a drop-out, it was a "pop" in the exhaust. When the car is cold it stutters under acceleration, with the pops in the exhaust correlating with the skip I feel.

Once the car warms up, it seems to go away about 90%.

There's no Service Engine light. I havent' hooked my scan tool up to the car yet.

To me it feels like there's unburned fuel igniting in the exhaust, which would explain the pop. I've had bad plugs, bad plug wires, bad cap & rotor, all that sort of crap and it never seemed to behave quite like this, so I'm a bit hesitant to just throw a bunch of that stuff at the car.

Does anybody have any ideas for what I should check?

Thanks.

 

Yeah, I do buddy...check the Vette forum


Sorry, couldn't resist...

 

check www.corvetteforum.com

That's a site full of information for Vettes.

 

TPI=NO OPTI.

Jim, this may or may not be relivant but my acura does the same thing (pops), and it was due to a slightly bent valve. Sounds like a bubble machine or a fishtank at idle, kind of funny actually.

 

IT'S NOT AN LT1! Twice now I've been told to check my opti, which is why I avoided the corvette forum in the first place. 90% of their answers start with "well my mechanic said..."

91 Corvettes are TPI cars, and this site is usually the best place for help with TPI engines.

 

I'm really hoping that it's not a bent valve, although the thought has crossed my mind. I don't hammer the car, and it almost never sees redline, so my fingers are crossed that it's something much less severe.

Because it goes away when the car warms up, and because it's not a constant thing, I'm fairly confident that it's not a mechanical issue.

 

The funny thing is that when my car warms up, it pops much less, that was why I mentioned it. If you are easy on the car though, I can't really see how this would happen?? It is alot easier to bend a valve on a honda obviously when the timing belt snaps. I relate a pop to a miss usually though.

 

Maybe one of your valve lifters is going bad? Do you hear any clacking in the morning when you first start it up?