6K Miss ( Fd )
 

Hi guys ,
i have only tried this with the car at operating temp( water 80 C + ) oil 60 C +

free rev in neutral WOT .. 6K miss then keeps accelerating to red line
free rev <WOT .............. sometimes no 6 K miss to red-line
boost in any gear any boost pressure < 5.5K ...no miss
boost in any gear any boost pressure >~6K ... miss then continues .. ( i do not really insist on it continuing ,i let off )
ECU reset no change

stock ecu
full intake and exhaust ( hogh flow cat )
simplified sequential
injectors cleaned and flow tested < 5000 km`s ago
does this with 9`s stock plugs in all 4 ...
checked coils , within specs , wires also ( ~15000 km`s old ) ,
engine grounds are tight , clean , + additional
fuel pump rewired to get full Battery voltage at WOT ( rewired in the fuse box next to left shok tower )
new fuel filter ,
seems to leave a cloud of blackish smoke when this happens
no A/F reference ,
EGT`s Normal
TPS within spex
No CEL codes ..
steady idle,
brownish spark plugs when examined

.. what`s so special about 6K ?....


pulls very strong otherwise even boosting,max ~ 8 psi ( lowered boost until i figure out problem )

any input .. ideas .. suggestions would be much appreciated

thx




a few hours later


came back from another run ...
changed coil pack ( all 3 ) with previously working , all test good ,
changed plugs to b9egv .035" gap ( which i used previously with great success boosted up to 13psi )

same problem

boost = 8psi

1st i can wind it to red-line it will go no problem but miss/ backfire around 6 K
all other gears i can boost fine to 5.9k ...
the moment i go to +6 .. sometimes 6.5K RMP .. it misses/ backfires

once again no CEL ,not nothing

im gonna try a different ECU

i can pull fine in all gears hard between 5-6 repetitively no problem
but the moment i pas 6.2 K .. backfire and miss


car ran well previously ... no idea when/why it started as i have not really revved past 6k in a while ... ( 1-2 mo)

why aren't you running colder plugs?

in addition to plugs, i'd lean toward wires (not just ignition wires, but the actual electrical wires that run the ignition system - coils, reluctor wheel, etc.). there could be something amiss there, too.