View Full Version : new ko4, now misfires

08-27-2007, 11:13 AM
I just installed my new brand new ko4 with mtm software. I got all of the info from hoppen motorsport in florida. I also installed a 5 bar fpr, the spark plugs that they sent me, a new inlet pipe and a high flow cat from labree. Now for the problems. The car runs great down low and under 15 psi boost. As soon as it hits 16 -25 psi it starts misfiring. I got a CEL and a code for multiple misfires, cylinder 1 and 3. I reset the code and moved the coils around. Then I got the same codes for cylinders 1, 3 and 4. I am going to check the ICM tonight after work. Is there any other way to check the coils, using a voltage/resistance meter?
Does anyone have any idea what else could be going wrong? Any help is much appreciated.[headbang]

08-27-2007, 11:24 AM
ICM is not the problem or the misfire would only occur on cylinder 2

08-27-2007, 11:25 AM
also are you running a MBC because 25psi sounds very high for normal K04 programming hell PC-16 wont even hit that without a MBC and thats a very agressive file. For that much boost you may want to look in to NGK BKR7E plugs since they are a range colder

08-27-2007, 11:34 AM
Your spark plug gap must be causing the misfires. I remember buying Iridium plugs for dirt cheap from someone who had K04 and it was giving him misfires but ran perfect on chipped K03.

08-27-2007, 11:41 AM
Yeah make sure your spark plugs are gapped at .28.

08-27-2007, 12:36 PM
The plugs are bosch FR5DP1 cold. I dont much about them. They are what the guy at Hoppen sold me. I have tried to contact him, butI havent heard back.I will try and gap them tonight then. I am not running a mbc. I have the stock n75. I checked that to make sure it was clicking and that it had the right amount of resistance. Any other Ideas? Thanks

08-27-2007, 02:45 PM
spark plug gap. typical problem.