irishguy0224

iTrader: (3)

Alright, so i went Vortech on my Z over the winter and the install went pretty smooth all in all. During the initial install i put on Berk Test pipes. Upon my first start on a base tune my car at idle was only pulling -5 vac on my boost gauge (autometer). I didn't think too much of it at the time and started my tuning process. About 600 miles in i decided the car was far too loud with the test pipes in for my preference and switched out to Berk HFC. Install went smoothly as it is pretty straight forward. Immediately following the HFC install my car started fouling plugs and threw a p0300 code for random cylinder misfire. Originally the car was idling like absolute crap. My tuner pulled some fuel from the tune at start up and it evened itself out for a bit but still was throwing the code. I can notice some slight fluctuation at idle, but nothing too bad. I was hoping that after putting some miles on the car it would clear.... Here we are 200 miles later and it's still there. If i clear it with Osiris it comes right back on after a few miles.

At this point, i have replaced all plugs and coil packs. I have taken the whole SC kit off and re-did all couplers, pipes etc to check for possible vacuum leaks that may be causing the code while also contributing to my low vac at idle... Still no change in either the code or low vac. I pulled the cam sensors last night and both were fine with no oil in the connectors.

I am at the point where i don't know what else to try or to check. Facebook pages haven't told me to check anything that i haven't already. I am going to smoke test it tomorrow and see if there is something i am missing vac wise... but does anyone else have an idea of what could be causing this misfire code? Any help would be seriously appreciated. I can't get my car inspected or finish my tune until it's taken care of.

NissanTracker

iTrader: (8)

I was just helping a buddy a couple days ago on his turbo Saab. Crappy vac. It ended up being his Fuel injector seal. It wasn't seating properly. The vortech comes with upgraded injectors, so this could be an area to check.

iideadeyeii

iTrader: (6)

Did you have colder plugs? My stock iridiums fouled after advancing timing(7-8lbs of boost) and I installed +2 colder copper plugs in their place

irishguy0224

iTrader: (3)

Can check the injectors. I have GTR injectors in there now.

Yea i have some colder plugs in

OldManZ350

iTrader: (23)

So you installed new injectors.... And you had the Intake off.

Did you verify that the Intakes is sealed and not leaking Vacuum?

I've had a Vacuum leak at the intake gasket, and thru the top intake mounting bolts before. It's a common place for a leak.

irishguy0224

iTrader: (3)

did a smoke test, not a single leak to be found anywhere in the engine. Started the car, unhooked my boost gauge read zero. plugged it back in.... right to freaking -19.... UNREAL.

Cleared the p0300 with osiris and will see if it comes back. If it does, it has to be something related to my HFC

Boingo

Do you have oxygen sensor bung extenders? If not, I have heard a few people say they helped eliminate nuisance codes. The p0300 comes and goes for me (test pipes). No issue with operation, idle, etc. I checked all the same stuff - to no avail.

irishguy0224

iTrader: (3)

Yea, both the HFC have the bung extenders on there. Never got a code when i had the test pipes on there. Going to pull the HFC off tonight and likely pull the honeycomb from them since Enjuku is being completely useless as far as help is concerned.