What I thought was stripped plug holes turned out to be the stupid header bolts backing out. So I need to fix those but I want to know if anybody has found exhaust leaks to be the cause of a low end stumble. Very light load light throttle low rpm I get a stutter. Sometimes it is worse than others and sometimes it's not even there. It happened about the same time I put my headers in... That's why I think it's the exhaust leak. Is there anything else I can check? The car is very well taken care of, freshly seafoamed, new o2's, clean MAF and intake...

 

I drove with an exhaust leak for months and never noticed a hesitation, so from my experience I don't think so. I'd check your spark plugs and wires.

 

What if the leak is from a spark plug hole? The thing I don't get was if it was a plug/wire it would not run good at WOT right? It runs like a ****in beast at WOT.

 

Wouldn't the leak set off the KM, retard timing and cause a "hesitation" sensation?