32 Misfiring/ Hesitating

[Morgz32]

hey guys

tonight whilst driving my 32 i noticed that once it comes on boost it starts hesitating/ misfiring abit and a cloud of black smoke out the back. I put $20 of BP 98 in it before hand and thats when i started noticing it and thats the first time it happened, the night before i went on the Antilag cruise and again put fuel in before hand and it had no problems came on power fine and smooth.

the car has splitfire coil packs with standard BOSCH plugs, forward facing plenum with saard injectors and a 35R turbo with 44mm gate

im thinking it could be a bad batch of fuel?? possible coil pack?? and maybe the standard plugs have given up on life and thats causing the drama

it idles fine, drives fine with no misfire but as soon as it creeps up to about 4-4.5rpm as the power comes on thats when it starts to hesitate and misfire, sometimes its not bad then some other times its pretty bad any suggestions????

cheers

[DVS JEZ]

How much boost?

Check the condition and gap of the spark plugs, try running a smaller gap

[Morgz32]

18psi of boost

gonna smash new plugs in and see what happens, what gap size would use recommend?

[DVS JEZ]

18psi of boost

gonna smash new plugs in and see what happens, what gap size would use recommend?

.8mm

[XKLABA]

could it be just a bad batch off fuel you picked up ? I ask cause you said you only noticed it after putting in new fuel

[Morgz32]

ill try gets some plugs with that size gap, and thats what i though but drove till warning light was on went to a different servo and still the same result.

I put a set of platinum plugs in it this morning that i had sitting around, so i put them in and drove it the hesitation is gone but still has abit of a misfire i looked inside each coil pack when i changed plugs and cylinder 1 coil had a white powdery resedue and the little coil spring inside is like gone and all other coils are clean and have no pwdery stuff in it, and the top of the old plug was powdery and all crapped up, so i have a feeling its a combination of shit plugs which are failing when hot? and a crapped out cylinder one coil pack? i think the connection between the plug and coil is not good and spark has to jum further hence why still has abit of a miss??

[Morgz32]

ok so i swapped a whole coil pack assembly for all 6 cylinders and the harness from my mrs's car to mine and took it for a spin, still the same result, like a popping, misfiring sound, doesnt really seem to miss i think i can rule out its a coilpack if mine runs the same with 2 different harnesses, i even swapped the dud looking one with the white shit in it to her car and took hers for a drive and hers ran nicely no miss or hesitation, im going down the lines that the pooping/ miss sound is maybe from the screamer pipe under abit of heavy acceleration??, it doesnt do it all the time when on boost just sometimes through the rev range, might even pay to get plugs with a .8mm gap??

[DVS JEZ]

How do the plugs look?

[Morgz32]

well the plug from cylinder 1, the terminal had like a white powdery substance all over it and same with the inside of the coil all the rest where fine but on some the insulator had like brown burnt marks on the bototm of it and around the centre electrode its all black with carbon build up, could this mean anything towards it having a misfire on boost??

took it for a drive with my original splitfires in and new platinum plugs and its the same on boost seems to have like a misfire/ backfire/ popping effect could this be tune related?? is it best i take it to a tuner to run on a dyno to see if they can spot any bugs??

could a air leak cause it to wanna miss on boost??

[Morgz32]

whats got me stumped is that i changed plugs and the hesitation had gone but still it seems to have a misfire/ popping/ backfire affect i changed the coil pack loom and coil packs over and no difference i even put mine on my gf's car and hers still ran nice and smooth with good power delivery.

so that kinda pulled me away from it being a coil pack issue, im even thinking it could just be it backfiring out of the screamer pipe, the car still goes hard, i was thinking even maybe a air leak in cooler piping or vac lines? its been raining here in perth and my AFM is in cooler piping so maybe water could of stuffed it up causing it to make the tune out of whack whilst i was driving it through puddles etc?

could be something as simple as i just need to get plugs with a .8mm gap?