I have or should I say my wife has a 97 GT that I recenlty replaced the intake manifold on (Doorman W/aluminum crossover) The problem is since I replaced the manifold it has developed a random misfire.I have replaced the plugs and one coil .I replaced the coil after using a spark tester and it appeared weaker than the other coil plus when I got it off it did have a crack in it!The misfire only happens when the engine is warmed up, it doesnt do it until then .It is a slight misfire but a misfire none the less!Any advice would be much appreciated !


Thanks in advance to any replys !!!

 

sounds like a air leak when the motor warms up it expands causing vac leak?? do you have a hiss sound?

 

Nothing that I hear so far .Thank you for the info though!

 

I would try to spray carb cleaner around there to see if it revs up easier to determine if you have exuast leak

 

I will give that a try .I took all the injectors out and cleaned them and then added injector cleaner to the tank and now it seems to be 98% better !No misfire but a little stutter for a split second on the bottom end.Thanks for the idea !A mechanic that my wife talked to today said the Bosch plugs that I put in could cause that stutter he said Autolite or motorcraft plugs only!(one in the same)The mechanic cleared out the random missfire code and it hasnt returned yet!(cross my fingers)Thanks again!