I just installed a 87xxx mile LT1 out of a 1994 Trans am in my third gen.....it ran great for about 150 miles then just all of a suddon it started cuttin out and poppin real bad in the upper RPM range..........I replaced the fuel filter and it helped but it still does it......could this be the optispark, injectors, what could this be????? HELP ME NOW!!!!!

 

sputtering in the upper rpms would be the opti, thats my guess...those aren't the most reliable ignitions

 

Especially if its the older design... They revised it around 95-96 to vent properly..

 

be sure to check your fuel pressure. my buddy's 96' did the same thing and he too ruled the opti bad. i took a look at it and the pressure was low. if the pressure is good, then on to the opti. it's a good possibility the dist cap center carbon has worn down or worn a hole in the rotor button. the latter happened on my 94' Formula. it had 96k.


as mentioned the 95-97 vented design is by far superior to the older 92-94 orginal non-vented design.

 

Sounds like the opti to me. I have helped diagnose and replace prolly a dozen from guys around here in the local car club. Upper RPM popping studdering etc ends up to be OPTI 9 out of 10 times. Check all wires, FP, etc before you do it though..


also when you order, get ahold of a guy named Jason Cromer over on CamaroZ28.com. That is his name, but I can't remember his board name. He can get you the opti for wholesale... tell him you are a Cz28 member and he will hook you up...