Ok so my car was running great, i went ahead and changed the spark plugs cause i kept cracking plugs(bosch) i replaced with acdelco 41-906 which is factory replacement. After replacing the plugs i noticed the car running different. then started misfiring really bad. I dont know if it was a wierd coincidence or what but my car started to over heat and i pulled over to find that my radiator hose was off. so i let it cool down and refilled it. not overheating anymore but misfiring really bad. Going down the highway i could only do about 45 cause of how bad it was and the car was shaking really bad. Then thought maybe the wires got switch by chance but i double checked them and they arent. i took all the plugs out and regapped them. (recently replaced, radiator,starter,opti-spark,water pump, plug wires,coolent sensor,and coolent switch,) i dont understand what is making it misfire, like i said, ran great till i replaced the plugs. took it to a shop and they said gapping was off on the plugs. but i double checked them and they arent. even numbers are misfiring(2,4,6,8) please help.

 

also when you rev it up black smoke comes out of the exhaust!

 

Is it possible the leaking radiator hose soaked the Opti?

This post really looks like it should be in "LT1 Based Engine Tech".

 

The opti didnt get soaked. I believe my cold air intake sucked up some coolent when the hose popped off. yesterday we took off the intake and sprayed the hell out of the throttle body with throttle body cleaner and got the car running pretty decent. Then today on my way to work it started acting up again. like it was plugged up,hesitating really bad. I checked the cat and its not plugged up. Im debating on running sea-foam threw the brake booster vacuum line and threw the gas tank to clean the injectors and everything. Any input would be nice.

 

i also just replaced the mass air flow sensor thinking maybe it got messed up when the coolant got sucked up