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hey guys, so this is my story. sent my car (r33 with rb25det NEO) to get services. got oil, plugs, filters and even o2 sensor changed.

got the car back, all sweet. next day car developed a miss on idle. it was missing only on idle ( would not miss under load, even on high boost). thought he may have used the wrong plugs, so i took off d plugs (noticed they were all black and fowled) and replaced then with ngk 6's gapped to 0.8. Started her up, and she was running fine. NEXT DAY, that miss on idle returned, and was getting progressively worst. :P however, when driving its fine.

i then decided to take out the plugs again, and see what the go was. when i took out the plugs, i noticed that, once again, all 6 plugs were BLACK and fowled. so i think its safe to say that the car (for sum odd reason) is running hella rich, and therefore fowling all the plugs.

now, only thing i can think of is maybe a shagged fuel pressure regulator. other then that i got nothing :ermm: . can anyone suggest any other culprits that could contribute to fowling all 6 plugs that quickly :down: .

MODS list:

-3inch turbo back exhaust with high flow cat

-ebc (0.6bar low, 0.9bar high)

-Power FC

-arc induction box

-fmic

everything else (injectors, fuel pump, coils etc) are stock standard

any help would be greatly appreciated guys,

cheers

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it wasnt doing it prior to servicing. nor was the tune played with. fuel economy has always been terrible. was getting bout 250km per tank, hence my reason for changing the o2 sensor. but other then that, neither the cas nor the tune was played with

mate i got no clue how to do that lol. if anyone knows how to do that and can meet me sumwhere etc (ide obviously pay them for their trouble) ide really appreciate it.

any other ideas other then it being tune related? just seems odd to foul up, brand spanking new plugs (all fo a sudden) in a day.

well i think its safe to conclude its runing rich without putting it on the dyno (shit fuel economy, plus spark plugs getting fowled hellas quick). i dnt want to pay some bloke 100 bux for his time on the dyno to tell me my car is running rich. my question is WHAT could have happened since the service that is causing it to dump so much fuel and therefore fowel plugs in one day.

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

If so, fuel reg is 99% the culprit :P

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

One other thing - Is this powerFC tuned? If not, I don't know why people bother installing PowerFc's and not tune them?

To me thats a waste of money. Its like buying a TV and listening to a radio station through it, and not actually watching it?

Also, running an untuned Powerfc is dangerous, they have massive timing and heaps of fuel. Not exactly safe.

hey man..... first thing.... dont waste your cash ..... its not the o2 sensor.... now do u get white smoke when u gun it? u pull out the spark plugs and their covered in oil and all black? could be the same problem as i have..... if it is DO NOT drive the car with any boost over 5lb...... as if could make the problem worse...... Where u from man ?

i had the same problem... the could would sound like its skipping a idle .... and when i gunned it white smoke would come out exhaust....took no notice of it until it got worse n worse.... what it was in my car was a damaged piston.... which then caused oil to go down thru the manifold and spray oil out the turbo...... If your in melb let me know undo one of the clamps holding the intercooler piping and check if there is some oil in there..... If there is thats your problem

ahkk thats good then.... disregard the post i just sent then...... what i done when i change my sparkies is get a rag with screw driver and put it down the plug and cleaned in there.... drained the engine of the oil(old) and put in some new... started car to move oil around.....drained the rest then topped up the whole thing with new oil.... its stopped the skipping idle and sparks were cool......

Edited by zeko33

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