After a full day at the shop doing diagnostics the problem has been narrowed down to either another bad poppet #4 or a bad lifter..Whats the chances of 2 brand new spider injector assemblies having the #4 poppet bad? if it is i need to play the lottery lol.. as far as the lifter goes the only thing i can think of at idle its not getting enough oil causing valve to not open properly causing a misfire..The scan tool was hooked up while driving and the misfire goes away under load or as soon as the throttle is reved up..so i am going to take the upper plenum back off and swap #2 poppet with #4 and see if the misfire moves to the #2 cylinder..If it doesn't ,back to square one and replace the engine again which is still under warranty. I'm so sick of this problem!
Does anyone have any thoughts to this?

 

I'd say slim to none and put a dollar into the lottery for me! LOL

Have you checked to make sure that there is no exhaust leaks?

 

all the exhaust gaskets are new and there are no leaks. as for what you said earlier about a case relearn and getting a re flash please explain what the difference is between the two...Thanks

 

A flash is a complete reprogramming of the PCM. A CASE relearn is simply a teaching procedure for one value that does not involve any actual code changes, just a stored value change.

 

Oh and i just wanted to ask your opinion on the lifter..Is it possible?Ever hear of this happening?

ok thanks for the clarification ..because when i mention case relearn they look at me like i have 3 eyes..LMAO!!

 

The lifter is a possibility. I have also seen a wiped cam lobe (where the cam lobe flattens out decreasing lift).

 

Thanks..I will diagnose the poppet in the morning and post results.

 

ok an update...i swapped #2 and #4 poppet and took it for a 40 mile drive...seems to idle better and much better throttle response and no SES light so far...UMMMM ok im lost! Swapping legs could be the issue, i just dont understand how...will see what happens through out the day.

 

Thats odd but what the hell hope it works for ya

 

Yes i agree it's very odd..Still have a slight rough idle almost like having a lopey cam lol But still no SES light..Could it be possible poppet#2 which is now in position 4 has great spray and compensating for a bad lifter and a weak poppet #4 now in 2 but with a good lifter, is balancing everything out? There are no engine noises at all