Pfc, Power Cutting Issue...

[Perry]

Hey guys,

Haven't had any drama's up until recently, but all of a sudden all sorts of issues.

Car was mapped on 23psi peak with 21psi taper no drama's about 12m ago.

The past month, now as soon as boost hits ~22.3psi, the car slams violently forwards, like a boost/fuel cut.

When this happens, the Defi boost gauge will spin back from 1.5bar to 0 then backwards again etc.

Now the curious thing is there is plenty of fuel, walbro pump and the injectors are only ~85-87% IDC, there is NO KNOCK at all when this occurs (15counts or less)

I wasn't aware the PFC had a boost/fuel cut of sorts??? Or am I wrong?

I've pulled a degree and added 3 counts of fuel across the whole map, still the same problem...

Am running a Blitz id3 EBC, which i've had to fiddle around with lately as its spiking stupidly in the cold, even with teh gain on like 7 instead of 12 it still spikes 1-2psi at 20.

Have swapped ignition leads with another working set, and have new plugs gapped correctly....

Any more ideas? doing my head in! Can i check the coilpacks with a multimeter?

BTW, its an Evo 7 which runs wastespark setup on 2 coil packs, i'm posting here cause theres alot more knowledge on PFC here.

Cheers guys

Ben

[Bennett]

Theres heaps of PFC info on sau if you search. Pretty sure they dont cut boost or fuel at any point. You can check coilpacks with a multimeter but i cant remember what they are supposed to read (You will find it if you search). Let me know if you find wat the problem is as i now have a huge missfire that feels like a boost and fuel cut at about 5000rpm. Probably actually boost related like you say ill have a look next time i drive. So could be same as your problem. It also happened when i moved to wasted spark setup cos my coilpacks kept missfiring but this is even worse now than it used to be.

[paulr33]

check the PFC FAQ and double check everything - look for loose mechanical items, look for loose hoses etc etc

the PFC will perform fuel cut if the following items are true

1) if you hit the std rev limit set in the PFC (viewable setting, ENGREV)

or

2) if you have the boost kit enabled (on by default) and you exceed boost target by 0.25kgcm2

so its likely #2 in your case, disable the boost kit if its on and try again

[Bennett]

I have disabled the boost kit (Car wouldnt eben start with it enabled) and its not hitting rev limit.

I put the stock ecu back in and it still does it... if that helps

[paulr33]

id say its something mechanic or a hose is buckling under pressure

[Bennett]

Took out spark plugs, cleaned them, then put them back in and car ran fine for 30mins and reved right out, then when i was about to change gears it made 3 loud pops and then took off even harder. Was running better than ever for another 15 mins. Then left it idling for 2 mins and runs like s**t again now. missfires under any load at all now. Cant seem to work it out, something must be fouling my sparkplugs...