Terrible stutter "misfire"

[milz]

After installing my new boost controller, and doing a few runs in the country to get the psi where I want it. Did not go past 18psi. When I was driving back home, was not driving hard, just cruising. All of a sudden it started, what sounded like misfiring. WTF The idle is rough. It sounds like it is running on two cylinders. We swapped fuel rail and injector setup, and ignition plugs and wires. Still no go. All plugs are firing though. Hooked up my friends data logger, and nothing out of the ordinary shows up. No loud or out of ordinary noises coming from the valve train or anything like that. The engine has less then 10k miles on it. if anyone know whats going on that would be sweet!!!!!!!!!!

 

[milz]

its a hallman pro rx. and yes i checked everything 3 times even read the haynes manual 3 times. idk whats wrong

 

[milz]

The check engine light never turned on? anybody think ecu? i own a aem standalone ( never installed, anyone know anyplaces around Wisconsin)

 

[Irrational]

Check your intercooler piping for a blows cupling

 

[ddavisaf]

http://www.vfaq.com/mods/ICtester.html
Boost leak test.

Smell your ECU for a fish smell. a.k.a. leaky caps.

What kind of plugs are you using and what are they gapped to?

 

[ddavisaf]

Walbro 255 high pressure

Do you have a FPR?

 

[milz]

i had the caps replaced on the ecu!! no i don't have a upgraded fpr!! it worked fine for like 3 months with out one. its still stock injectors, and frp.. i had ngk plugs they had a R on them. i asked them for 2 steps colder and it work great.. i just put some Bosch plugs in it was the only thing the part store had. i can get the part number if u want! but I'm at work right now!

 

[ddavisaf]

You put Bosch plugs in.....

Well, first your fuel pump is over riding your stock fuel pressure regulator. Doesn't matter if it's functioning or not it's still bad.
Second, Bosch plugs are about as bad as you can put in our cars.
NGK BPR7ES for you and you'll be good. If you need colder than that (which you don't) BPR8ES.

 

[milz]

i was running ngk bpr7es when it happened!!

 

[milz]

i just ran a compression test results are NOT looking good!! 150, 150, 75, 25
thanks for everyones help. but it will need another rebuild

 

[talonTSIDriver]

Dude, sorry to hear that. I know how that feels. To bad insurance does not cover blown engines, haha.

 

[ddavisaf]

i just ran a compression test results are NOT looking good!! 150, 150, 75, 25
thanks for everyones help. but it will need another rebuild

Before you jump into anything.

Check your timing.
Get another tester and retest all four cylinders.
Your compression is that low and you weren't smoking or anything?

 

[milz]

No not at all! the car never smoked even when it broke!

 

[ddavisaf]

Whats the timing looking like?

 

[milz]

Whats the timing looking like?

Timing was perfect!!
blew a headgasket
Im glad its all over with now, and i have my standalone ready for the dyno.. i will post my print outs!