Ok, I have to pull the maggie off for a third time. Looking for the same thing.
Drove to Atlanta this weekend to have Vengeance Racing tune the car. We were pretty sure the mis and surge was in the tune, and so I went up to have it re-tuned to stop doing it.
Well, he couldn't get the missfire/surge to go away. Couldn't find a leak. But he says there is one and that's why I'm having the problem.
Made the same dyno numbers as original but added 10 in torque. (470 rwhp - 480 tq) pretty much.
So the leak must just be at low rpm???
At any rate; Somebody tell me what to look for. Most likely places to find a leak. Mike, at Vengeance, said the back side of the vacuum hose going into the heads (the one that goes into the rear of the driver side valve cover that the catch can connects to) is leaking. But that's not what the problem is because it didn't get better when we plug it off.
So I have a leak somewhere.
I've already done just about everything imagineable, but I'll just do it agian, again, again. I'm hesitant to spray carb cleaner by the headers, obviously, but I will.
So, any suggestions as I go through this again.
You post it, I'll do it.
List of things I'm going to do already, I'll proceed to the next unless I find it.
1. Cut a 10mm socket down to fit the bolt under the rear drive pulley and get better torque on it.
2. Remove hoses and plug the hose stems completely. (If the miss goes away I know it's in the hoses)
3. Carefully spray carb cleaner around the manifold.
4. Remove the bloser and replace the gaskets.
OH, ya. Car runs like a beast when it's up in the band. But it's died 7 or 8 times now. Twice pulling out into traffic. Pissed a guy off pretty bad. He was laying on his horn. lol
UPDATE: Turns out it was a header gasket leak. Go figure.