Hello

I'm hoping someone can help me with my misfire issue.

the problem is I get a series of what feel like misfires when im in high boost.
It does not always happen but it does happen most of the time.
it happens a little at 6psi and lose all power at 10psi.

The most odd thing about it (pretty rare to happen but I can make it happen by keepign my foot on the throttle while it misses) is it sometimes continues to happen for 100-200 meters down the road after the revs have dropped and I get back onto the throttle to keep the car at cruising speed (hope that made sense)

about my car:

na6
diy t25 turbo kit
COPS
diypnp
rx7 injectors


things I have tried to fix the problem:

-changed spark plugs (although it was to old warmer plugs from before the turbo conversion)
-bought another toyota coil and tested it in each place
-rewired my cops harness
-added in cops capacitor
-looking through my datalogs to see if anything is indicative
-crying
-regaping the plugs

things to note:
my afr doesnt go very rich or lean before the misses
my battery is sorta on the way out


I have no idea what to try next (I do have brand new ngk bkr7e's ordered to replace the current bosch ones) I am not even 100% sure if its ignition related I think there may be some kinda protection in the ecu as it has the misses after the even occasionally like stated above.

thanks for any help.

I can post up a datalog and my tune if people think that would help

 

of course it will help.


first thought is overboost protection.

 

overboost isnt it it may be there in the log i'll post in a min but the overboost has been set at 230kpa when I was running 6 and 8psi when it was still happening and I seemingly had no boost spikes.

and doesnt really explain why it does it for a bit after the acceleration event sometimes.

 

ok here you go...

the acceleration event was at ~390 second mark (it starts at 50s for some reason)

had to compress the log as a rar file cause it wouldnt let me upload an .msl file sorry for the hassle

 

heres an old datalog that is easier to see.

theres no after the fact misfire

it was on lower boost at the time so there was less misfire. but that makes it easier to see

event starts at second 507
log starts at second 219

 

it was the plugs

protip: dont buy bosch platinum plus sparkplugs for a turbo miata.

even making the gap smaller hardly helped.

now running bkr7e and all the misfire is gone.

now to tune for 15psi