top of third gear at about 4500 rpm it stumbles and if i keep it to the wood it will get over the hump and shift into overdrive, it takes like 2secs of stumbling, i have checked fuel pressure (good) and i read about a guy that had the same problem and it was his injectors, did that and it still does the same thing!! nothing has ever just worked good with my z28 and i am very frustrated!!! i hope someone can help

 

The opti is always brought up in these topics so that might be your problem. How old is it?

 

about a 1 1/2 years old

 

i am going to pull a spark plug and look at they are less than a year old i changed them for my nitrous setup. if anyone has any ideas i would appreciate it!!

 

well did lots of searching and lots of people have had this problem, wires, opti,and coil seem to be most of the problems



mine started after my lt and 3300 stall install. i am going to look at the plug and wires better ( i will lift the car up) i would guess it has someting to do with my plug and wires with the lt install, i drove the car like 100 miles with open headers and had no miss, when i had my stall installed on the way home it started (i drove my car to the tranny shop open header) i have read for 3 hours now and i am sleepy so i will continue my quest later!!!!

 

Not long after my headers where installed i burnt a plug wire and had a serious performance issue until i replaced it.

 

was it touching the header?? where was it burnt at??

 

yea i would definetly check plugs and wires first. Opti could even be the culprit but i'd leave that as last option. I've had this problem on 3 different occasions and each time it was something different so it could be a number of diff things. But like i said, rule out the easy, inexpensive stuff first. The plugs and wires are the first obvious thing to check. If it started happening after the header install, check for a header leak. The owner before me drove the bolts in sideways and the headers weren't clamped down enough, giving me a header leak, so make sure . Make sure there are no rips in your intake elbow and make sure your MAF is clean and working properly. It is amazing what unregistered air can cause. But if u have a scanner check your O2 values, they are common to go especially with headers, and im sure the nitrous has an effect on them.