Help: Plugs Keep Getting Fouled

[The Mafia]

and I bet the powerfc is tuned for full power only, and none of the cruise, low or medium load have been touched.

Thats what tuners do these days, on the dyno, do the full power curve, and then charge some poor prick $800.

[autoworx]

check for vacume leaks

[QUICKY]

mate it very wel could be the tune, but i dont think the person who tuned it wouldnt have taken his time doing it properly. it was a reputable workshop. and the car was tuned last about 6 months ago. and hasnt had any new modifications. plus if it was the tune, why would it have been fine for the last 6 months, and only start fowling plugs in a day, after the last service?

only thing, other then the fuel pressure reg (working fine), that i can think of that could cause this sudden offset is the new o2 sensor? but can a o2 sensor cauz plugs to fowel up that bad?

[QUICKY]

will have a look for vacuum leaks. however, cars idle is stable and doesnt miss (prior to fowling plugs), and holds boost fine

ALso, i discovered i had a tiny hole on the hose going into the fuel filter, which i have now fixed. any chance that could have contributed?

[FloydWestwood]

i doubt it, flow would still be constant, maybe a little less pressure, and your engine would just be getting fuel sprayed on the externals.

[QUICKY]

thats what i thought . well anyone else got any ideas?

[FloydWestwood]

you havent put any additives in your fuel?

[QUICKY]

na course not. i only ever run bp ultimate or v power. dont use octane booster or any other additives

[R31Nismoid]

Well if the fuel reg wasnt it

get on the dyno and get AFR print outs.

[QUICKY]

yeh this weekend, im gna borrow my mates afm and o2 sensor, and see if the spark plugs fowel up. if they do, then ill book her in for a touch up tune on monday. just wanna eliminate all possibilities before i spend money at a tuner

[GeeTR]

Don't mean to sound like a tosser, but what do the plugs look like? Been around since T-rex, but check this. Take a pic of your plugs, post it up for comments.

From my experiences, plugs in a modern car have to be obscenely dirty to cause a dodegy idle, maybe tis something else.

Edited August 1, 2008 by GeeTR

[QUICKY]

mate after one day use, they are literaly pitch black. there not oily though. thats after 1 day use. i dnt leave them long enuf to see how they look after a week or so.

[neo32]

so the regs not holding pressuere by this statement or is holding too much

Does it blow a cloud of smoke on idle if you free rev once warm?

If so, fuel reg is 99% the culprit

Just get another and off you go.

Can also be checked when driving if you have a fuel pressure gauge and feed it out under the bonnet

[QUICKY]

ok so i tried another o2 sensor to no avail. any1 got any more ideas?

[GeeTR]

Wideband AFR time maybe.

[QUICKY]

OK WELL ill explain exactly what happened today. i instaled new plugs and changed the o2 sensor. car was driing/idling fine, no misses etc. as soon as i gave it a hit on high boost (0.9bar). few streets away from mine. when i parked the car, it began to miss on idle (all plugs fowled again). im heading towards a tune issue, but i wanna cover al other possible culprits, so i dont have to spend too much money at the workshop, incase its not tune related

[QUICKY]

you guys were right, it was the tune. it seems the previous tune was tuned for the faulty o2 sensor, so when replaced with the new o2 sensor, it ran extremely rich and kept fowling the plugs. got a retune done today and all seems to be sweet

thanks for ur help, greatly appreciated

[neo32]

just a quick note with my tune the o2 sensor is turned off my understanding is that its only used to adjust idle and cruize maps?

[The Mafia]

Yeap, it turns off when you push the throttle, and turns back on when the throttle is stready.

THey need to be turned off when tuning, as they try and tune over the top of you.