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Help Pls, R33 Misfiring After Fmic Installation

bin

By bin,
in Engines & Forced Induction

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bin Community Regular

bin

Posted
Posted

Hi all, need some troubleshooting help from you guys.

As the title states, after I installed my front mount intercooler, I get misfiring from 5500 rpm - 6500 rpm. I don't think this is an issue with the coilpacks / spark plugs as prior to using the fmic, I had no issues with misfiring.

My mods are: a pod filter, 3inch turbo back exhaust, with a bellmouth dump pipe, and of course the fmic.

Running a standard computer without a boost controller. Car runs at 9.5 - 10psi at peak boost.

Someone please point me in the right direction to solve this problem.

Thanks and cheers!

Krishy Grand Master

Krishy

Posted
Posted

i would also suggest not to flog the daylight out of your atm.....RB25DET ecu's are self learning ECU's so it takes about 500-1000kms before it sorts itself out....so just drive it normally and also since you have a FMIC you may need to regap the spark plugs to 0.8mm.....also check if there is a slight leak anywhere....as that could also cause some issues....check all your fittings, vaccum lines etc and how is your stock boost controller fitted up???

hope that helps and goodluck mate

mad082 Grand Master

mad082

Posted
Posted
the good ol R & R, need a piggy back or aftermarket computer.

the search button is your friend

highly doubt it will be R & R as his boost isn't high enough, and it usually happens lower in the rev range.

i would say that it is a spark plug or coil pack issue. before you put the fmic on it would've been fine, but now that you are getting colder, more dense air into the cylinders it takes more energy to ignite the fuel, and the spark plugs/coils aren't coping. if you aren't running 0.8mm plugs i would try that first. if you are, how old are they? might be worth getting new ones if they are over 10,000kms old. if the plugs are 0.8mm and not very old, try cleaing the contact points of the coils (where the coil meets the spark plug) and also try taping them up.

Munkyb0y Grand Master

Munkyb0y

Posted
Posted (edited)

and to add to that list. if you have series 1 coils, they have springs in them. when you get the coils out, remove the springs, and stretch them before putting them back in. it helps make better contact with the spark plug.

you are probably seeing more boost now than before the fmic install. its common. hence the extra boost + weak spark = misfire.

Edited by Munkyb0y
bin Community Regular

bin

Posted
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Posted

Thanks for the feedback guys! I will try troubleshooting with what you guys have suggested.

Pal mentioned that it could be hitting R & R but Mad082 suggests that it issn't.

Can anyone confirm if R & R is a possibility or not. So that I can strike that off my list.

But yea, thanks for pointing me in the right direction guys, appreciated.

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