hey guys,
i have this issue with a costumer car, the car is popping and fluctuating constantly at idle no matter what AFR it gets, no matter the timing and no matter the injector offsets.
it does the same pop with CROME & NEPTUNE

some info:
obd2a car
obd2a to obd1 adapter
d16z6 STOCK
Y8 dizzy internals inside a TD42U housing,
NO CEL's
ultrasonic cleaned iace
fitv closed all the way in,
WRX 440cc injectors with good offsets(i played with the offsets and it dosnt help,

what i allready tryed:
tryed crome,
tryed neptune with and without idle ignition adjustments,
no vacume leaks
spark plugs
good fuel pressure
different ecu
tdc cyp ckp sensors area bout 375ohm
different coil
different ignition wires
different injectors (but still the same WRX)
replaced fuel filter



here is a video lease pay attention to +30:00 secs


muffler



any idea?
i'm going insane here,
thanks!

 

Try adding 5-10% more fuel in idle areas, decrease IACV duty cycle, then try adding 2-4 degrees timing in idle areas....

 

How's the plugs?

Gap/heat range? Condition?

Valve lash adjustment?

 

plugs are ok for now bkr6 stock gap, will replace them for 7's once i will fix the issue, lash is ok,

tried stock injectors and a stock map and the car works fine, no missing or anything even at 16.0 afr,

i think decided that the injectors are the problem,

funny thing is, that when i turn on headlights and rear defroster the car works pretty much ok with the 525's at 14.5afr, and when i turn them off the car starts to bog again, i messed with the offsets alot, and it seems that what ever i do the car will only miss with no electrical load at all, (no head lights no defroster)
BUT when i turn all the electrical components off(head lights and defroster) the car will only idle well @12.5 afr,
i also noticed that the car stops some of the missing when i put 1 degree in all the idle cells,

 

 

U need to adjust voltage vs dead time

 

just tried the car with stock injectors and it still pops,

 

if you know for sure there's no vac leak, it could be a TPS issue, bad MAP, too much tension on the throttle cable or too much gap on the idle stopper screw. could be a bad PCV or evap solenoid, bad voltage regulator or ELD. I would prefer to look at a datalog.
Alternatively it may be a main relay or injector wiring issue. I assume you have good ground connections everywhere.
could also be a valve or compression issue, I'd do a leakdown test if you can't find anything else.