so, i baught my car in november a 94 z28 lt1 and drove it through the winter, i live in pennsylvania so winter actually means snow and ice, so its cold, so the car never really had a chance to heat up too too much b/c it was so cold out.
well in the spring my problems started.
the car runs like a champ when i start it and drive for a while...
once its warm it turns to crap. it starts to sputter around 3k rpm and the more i drive it the lower the rpm gets for the miss to be noticable..
its not a regular miss, like a bad plug, its a huge miss, if i gunned it while cruising the miss would make the rpm go from 2k to 5k and bounce with no power...
i have changed the plugs, i figured id start at the easy part and see what worked. plugs didnt work, so i took it to a good shop, they scanned it and i got nothing, i had codes for a short in the ignition wire but idk if that would cause this, there was no codes for the miss though. after more scanning and whatnot there was something wrong in the computer where it would send a signal to the temp sensor but it wouldnt get one back, i had it flashed and they said everything took and it was like a new computer .... i thought that may fix the problem but it didnt.
when i took it to the shop and had the guy run it till it missed so he could see b/c its hard to explain, i noticed that the cat was literally red hot, the tranny was boiling hot and there was a little coolant leaking out, dunno where the car was lifted and we wanted to let it cool before we dropped it so i didnt see where the coolant came from....
sooo, i think the red hot cat was from it missing and pushing excess gas out... not too sure on the tranny getting so hot... not so sure on wtf is wrong in general,
Someone help before i pour more money into this and dont solve the problem.

 

These type of issues can be tuff to figure out with the car infront of you. But there is a common LT1 issue. Do a search on "Opti" on this website.

 

so its not one cylinder but the motor dies? when it misses or cuts out does the tach drop to zero before the engine stops turning. like does it instantly go to zero or jump very fast? like gorn says it could be a number of things. your going to want to start checking as many connections and wires as you can. look for the obvious first like wires close to the exhaust or sharp corners, corrosion on wires or connectors, stuff like that. the pink and black wire seems to be a ignition related wire everywhere in the system. makes a guy wish it would die at least then you could look for it.

 

have you done anything with o2 sensors? you're saying it starts cutting out when it gets warmed up

 

well to start i should have mentioned two things, the only code i did get was a short in an ignition wire somewhere, but what i checked wasnt bad...
and the lt is out of something else, idk what or what year so ill have to do some searching before i know exactly what it was and what year then i can change the opti, i was hoping not to but gotta figure this out soon.
ill scan it again since i put the computer back in and see, then ill check for ignition problems and change the wires and opti...
as for the problem, its only died once i think from this problem and that was when i had to drive it somewhere to park it after it acted up and the miss was to the point where if i gave it gas it would jump all over the place... everytime ive drove it since though i didnt let it go long enough for it to shut off, its something with when it gets warm, like a few of you have said, maybe a wire, idk ... just shooting in the dark right now...
all i know is if i turn it off when its acting up, and let it cool, itll start up fine and run like a champ til it warms up again, so idk what else it could be since its only when it gets warm... any other suggestions are greatly appreciated..

 

also im new to the site but ive been searching on it for like 5 months now on other peoples problems that sound like mine, ive only found one other guy that has the same problem and nobody gave him an answer that worked or he didnt reply that it worked, so i havnt seen anyone else with this problem that got it fixed.