when i blew my engine up i thought nothing of it but at idle you can here poping and misfire... it never affected anything on data logs nor hpt data as ive been through 2 tunes.... when i put the new engine in as soon as i drove it it sounded like it had a spark plug missing... so i changed the plugs to my lt7 iridiums i had in on my 6 psi tune... same thing... so i bought new plugs and changed i m and coil and same thing... then out of no where it completely stopped and ran fine for 2 days...then today it did it randomly and cleared up... it did it under idle as well as boost but always goes away... im on brand new plugs and it still pops under idle.. gapped to 0.28....is there a better solution to spark setup? ive tried to research 2200 coils and im thinking of trying that route cause its keeping me from turning the boost up as this is likely the reason cyl 1 exploded...

Sounds like a Modus scan tool is in order here, something on your HP Tuners will also show this, just because there is no check engine light doesn't always mean nothing is wrong.....

I had this. Had plugs that looked fine, put new ones in, its been golden. I also found that one of my plug boots was bent and getting new ones helped the problem a little.


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i do get cel i get p300 random as well as cyl 1 misfire... but its always one or the other depending on what it feels like throwing that day... also flashes once in a great while of course as soon as it flashes no matter what i let off the throttle.... sometime in 5th gear decelerating the wideband bounces in the 14's instead of going straight to 0..... i ordered 2200 wires and icm and coils.... i can sometimes hear what sounds like arcing... i think im gonna change the gap to .032 and see if that helps...i have the same misfire even if i change coils and plugs... someone said run a better ground to the head but i didnt think that the coil got its ground that way.... like i said data logs on hpt and my current tune dont show whats happening for some reason...

Do you think it has anything to do with the 25-30 psi that you are running out of the saab set up?

swap out your ignition module and see if that fixes it. its an expensive part so if you can find a friend or a family member with one that would be the easiest.

read first before posting... im not running 25 psi a spike is not running pressure its a spike... ive changed plugs and coils same problem... i can tell maily at idle where obviously boost isnt affecting the isle since its not under boost.

Mine did the same think on cyl. #3 before. I change spark plug etc like you and it don't solved my problem.
I guess your fuel trim are in the positif Idle. In my case a just add fuel in Idle. From VE 72 Idle(with MissFire) to 80% VE in 1000rpm 80vac case and it's solved my problem.
Add Fuel (VE) in your good case of your VE Idle... you need more fuel .


Boost Lover

* Unequal compensation (CL) of your PCM due to lack of Fuel on Idle causes the Miss Fire.


Boost Lover