squeals99

iTrader: (8)

alright well my friend has a 94 z28... and he got it from some old lady for like $200, but its really not a bad car at all... interior is fine, only like 100k on motor and tranny, and paint is in good shape as well... he just found a killer deal really... but i think he has a problem of some kind with it that he cant figure out how to fix... the car runs great when it is cold, but as soon as the car gets to operating temperatures it starts sputtering and acts like it is running off of like 2 cylinders... he said that he can start it up cold, go do donuts like crazy, and on the way home it will basically die on him until he lets it cool, and then its fine to drive back... any idea what the problem would be?

TransAmdriv3r

iTrader: (10)

any codes ??? If I were him I would do a full complete tune up. Plugs, wires, filters ect and maybe even the opti and 02 sensors (water pump too while he has it off). older people typically will let their cars go because they cant do it and because it cost so much to take to a mechanic, so I would just take that extra cash he saved and go the whole 9 yards.

squeals99

iTrader: (8)

yeah i forgot about that part... he took it to the local gm dealer to have them see if they could fix it... they replaced the radiator, plugs and wires, checked all the electrical connections, and changed all the fluids... and they may have even changed the opti, but im not too sure about that... but he said they want to charge him $1000 to look it over the next time because they dont know what it is or somethin like that... ill talk to him to see what they did to it for sure this weekend, but i know he spent quite a bit to try to fix it and it didnt do the trick

Hackscamaro

I had the same problem with my 93. i tried swapping out plugs, icm, wires and i decided to go ahead and change the opti and it fixed my problem. my car was not throwing any codes whatsoever. but before changing the opti i would try and change anything you think may be related to the problem

93lt1n00b

read my tread i just had this same problem read thru it
https://ls1tech.com/forums/lt1-lt4-modifications/896550-lt1-huge-problem-when-warmed-up.html
it ended up being the optispark i bet money thats what ur prob is too

1997b4c

Same problem with my 97 b4c. I changed the opti to fix the problem.

Smokeshow_2006

iTrader: (3)

My 93 did the same thing when I first got it.
turned out to be the coolent temp sensor. Car would go into open loop, and the car would get rich, run like ****, and eventually die, untill it coolled off enough.