14psi its good, 15psi and it misfires

[volks88]

i boost leak tested again today just to re check everything before EPL sends me another ECU to try out. i found a small split in my boost gauge line and a loose clamp on the y split from the bottom of the n75. fixed those. still misfires. checked the wastegate lines and wastegates and everything seems to check out. now when i turn down the boost to 14psi it will not misfire and i cant get it to pull codes. now turn it up to 15psi and it misfires immediatly and the CEL flashes and it stores codes. ive replaced and checked everything. i really cant help but think this is a ECU/software issue . my car lost communication with the diagnostics 3 times and 1 time i couldnt connect. gas gauge is starting to sway (replaced sending unit 6 months ago), coolant temp gauge is weird occasinally. i hate this car but i dont want to get rid of it. so my question is could it still be the ECU? i mean wouldnt the problem persist regardless of the level of boost? update:::: ok so i regapped to .022 and turned the boost to 24psi and the fucking car pulls like it should. zero hesitation and.......... wait for it........ then it starts to stumble. slowly but surely. here it comes again. what the fuck! it cant be a leak if i can get it to run great for 30 minutes on 24psi and then it slowly stumbles. colder plugs maybe?

[exorcet]

have you done a leakdown test? i started to suggest spark plugs (due to higher boost = misfire = higher cylinder pressure blowing spark out) but then I realized it was YOU (yeah you!) haha..didn't realize at first w/ the avatar change.. so obviously you've been through the spark plug ordeal.

having been through almost the same thing as you i'm thinking i need to do a leakdown test..

[RolledMySTi]

I would suspect the ecu. My car ran great until I went stage 2+. I bought the car with a chip which I think was only a stage 1 tuning. In 1st I hit a drop in power around 4500rpms. I think this is because the chip can't compensate for the rapid rise in boost. Every other gear is gravy. In stock mode it runs perfect. I have no boost leaks and a new N75. With the problems you had and what I've had it leads me to think the ecu could be the cause of your problems too.

[RogueStatus]

theres no more leaks at all? sounds like when i had a leak but could only be detected in higher boost. i.e.- 14 psi doesnt open the tear enough to cause it to leak/throw code/misfire, but when it hits 15+psi it throws enough pressure through the hose to make it leak out. just a thought,your car never runs right haha.

[volks88]

ive tested up to 20psi and there are no leaks.

[RogueStatus]

hmm...weird...i guess just wait to see what that new software does

[volks88]

im running the bkr7e. i was thinking about switching up plugs. the reason i didnt think a leak was at first it ran great on 16psi but then after a while it started to hesitate so i turned it down to 14psi

[RogueStatus]

im running the bosch copper plugs from 034motorsport and they work great. try them. maybe the gap on them is wrong? did you make sure its not something stupid like ones not in all the way? im sure youve checked coils and icm's already..

[volks88]

im running the bosch copper plugs from 034motorsport and they work great. try them. maybe the gap on them is wrong? did you make sure its not something stupid like ones not in all the way? im sure youve checked coils and icm's already..

ive tried every gap from .024 to .028. coils, new oem. icms have been swapped around and swapped with another car. no change at all. epl had told me they have had to use a .022 gap before

[RogueStatus]

.22? i think mine are .32 haha

[volks88]

yeah who knows. im trying to hang in there with EPL but its getting tough . i mean 3 different EPL tuned cars all having misfires in the exact same cylinders 3,4 and 5??

[RogueStatus]

yeah bretts was,last i knew he was gonna sell the car...i actually havent seen/heard from him in awhile and he lives 5 minutes from me...hmm.

[Boris]

why dont you try the .022 gap then?

[Dr. Jekyll]

yeah who knows. im trying to hang in there with EPL but its getting tough . i mean 3 different EPL tuned cars all having misfires in the exact same cylinders 3,4 and 5??

I can tell you, it's not going to be the tune. I, as well as others, have used the OTS as well as custom tunes with no misfire issues. When I did have misfire issues, it was either my plugs or a vac leak.

I don't think it's even possible for a tune to cause specific cylinders to misfire.

Have you gotta any ECUx logs yet? Pressure testing and ECUx logs should be the first and second thing you do when you think you have a problem. Not only will the logs help us diagnose, but it will also help EPL determine the problem, whether it be a possible tuning issue or hardware issue.

The issue you are describing could be caused by a number of things. From a bad ECU, to a bad fuel pump, or a boost leak. Right now you are just guessing at what the problem is and placing blame on the easiest person to place blame on... the tuner.

I've tried to help you out, but for some reason you refuse to provide basic ECUx logs. And it seems like everytime you look over the car you find another glaring hardware issue. Needless to say, get some logs, get the car sorted out and then, if the problem is still there, maybe look at the tune. But 99% of the time, the tune is not the issue.

[quickaudi]

2nd, it's hardware

[volks88]

ok so i regapped to .022 and turned the boost to 24psi and the fucking car pulls like it should. zero hesitation.......... wait for it........ then it sarts to stumble. slowly but surely. here it comes again. what the fuck! it cant be a leak if i can get it to run great for 30 minutes on 24psi and then it slowly stumbles. colder plugs maybe?

[The_Jerbel]

Which plugs are you running? It sounds to me like you need to go at least one heat range cooler...

[volks88]

which Plugs Are You Running? It Sounds To Me Like You Need To Go At Least One Heat Range Cooler...

ngk Bkr7e.

[The_Jerbel]

Try using Bosch platin side-fire plugs.

[AudiSportB5S4]

^^ agreed. I gave them a try and they made a world of diff.

[volks88]

The issue you are describing could be caused by a number of things. From a bad ECU, to a bad fuel pump, or a boost leak. Right now you are just guessing at what the problem is and placing blame on the easiest person to place blame on... the tuner.

there are NO LEAKS! im not trying to blame it on EPL. why i said im trying to hang in there with them is the total lack of communication whether its email or phone calls. one of the reasons i chose there kit was that people talked about the great cust support. im waiting on a ECU from them and its been 2 weeks. simply just send me an ECU with their tune on it and i'll eliminate the ecu AND their tune if it doesnt fix it. if then and only then will i spend the $250 on ECUx. i also have a new fuel pump and wideband is showing great a/f ratio. car is at 20psi now with no hesitation.

[pizipe]

Have you eliminated coilpacks and all the connections to the coils and spark plugs? I had a mad misfire that drove me crazy (and also went away when I turned down boost) it ended up being the connectors to either the spark plugs or coils, I can't remember cuz it was a couple of years ago. Check those out.

[volks88]

Have you eliminated coilpacks and all the connections to the coils and spark plugs? I had a mad misfire that drove me crazy (and also went away when I turned down boost) it ended up being the connectors to either the spark plugs or coils, I can't remember cuz it was a couple of years ago. Check those out.

i have brand new coils. how did you find it?

[The_Jerbel]

Did you replace the tube conductors that connect the CP and the plugs? They are typically a separate part number from the CP and are not sold together.