I am having this issue and I cant figure out what it is at this point.

My IX MR has less than 19,000 miles on it and its missing after it does a couple pulls.
And it missed pretty much immediately when it gets into boost when launched off the factory launch control/ 2 step. (I rarely ever launch the car)

The car is tuned hits 24psi and settles around 22. It pulls like normal until the car has been running for about 35-40 mins.

I checked all my vacuum lines, etc and none are cracked or broken etc.

I just put Denso IKH24's in it which were recommended to me by my tuner. I didn't gap them because I dont have an iridium plug gapper on hand. But it did seem to help some. I have a Walbro pump that I am going to put in so if its the pump making the issue it will be fixed.

Any suggestions? Gap the plugs to a certain point with an iridium gapper? Could my coils be getting this weak this fast?

 

Didn't know they make an iridium plug gapper.....

Anyway, take them back out and gap them correctly. Plugs off the shelf are never the correct gap. Then get back to us.

 

^this

 

If they are a step colder plug, what should they be gapped at? Stock will work with it being a step colder?

 

im not too sure on this but i think you should be able to hear the difference from spark plug blow out and misfiring. I say if it is only doing it when your boosting then its the plugs for sure.

maybe you can throw your stock plugs back in. gap them to .22 and let it rip and see if it does the same thing. then you can rule out the spark plugs.

 

.22 is the correct gap.

Step colder is the same gap, just lets the tuner run some more timing.

Blow out of plugs usually happens when the gap is too large and you are boosting denser air. Note: happens a lot in the winter time. Just wait till November and see the posts about it,LOL

 

Alright sounds good thank you for the feedback. I'll gap them and let you know what happens

 

I closed the gap up to .24 and Im still having the issue. Would a .02 really make that much of a difference to go .22 or am I looking at something different like having to replace my stock coils?

 

bump need help still

 

i hope you didnt gap the iridiums. ive heard that you cannot re-gap iridiums.

do it to some stock spark plugs and see if that fixes it. do you have your stockers?


or try lowering the boost and see if the car does the same thing at a lower boost.

other than that you would have to move onto coils being the problem, maybe fuel pump.

 

You can gap any plug. Be it copper, iridium, or platinum .You just have to be careful at it. That's why there are specs for every car. Plug manufacturers just gap to a general range. Plus I never trust them out of the box, you every check the difference in gap!

To the OP, gap to .22
Ohm out the spark plug wires too

 

gap the plugs smaller just to try. and whats the status after the walbro?

 

I was missing under boost and it ended up being my plugs. I would also try the standard copper bpr7es's gapped correctly just to rule it out. They're very very cheap

 

* * * * Update * * * *

Walbro is in.

Plugs are gapped at .22 and also tried .24

Car still misses.

Put on a friends coils, still misses the same.

The battery has been cranking the car over a little slow in the past 2 weeks. Could the alternator be going bad, and not providing enough power to the coils under boost?

 

Dirty injectors?

Athanasios