Help! Blowing Smoke!

[shredder667]

ok, so my r32 gtr has blown black smoke pretty much since i've owned it. its only visible when it gets up past around 5k revs, but even if i don't do that and just drive sedately, by the end of the week that back of the car is pretty black. obviously the first thought is that its running rich and so far, its had a tune with a pfc, and afr is at a very lean 12.5 and had injectors checked and cleaned and its still blowing smoke. any ideas anyone?

also, i'm noticing a massive drop in mileage. i used to get 450k's from a tank and now i'm getting about 380 but that's only recent. its always blown smoke though so i don't think the two are related. cheers guys, any ideas would be handy!

[Gtrgodzilla67]

check the 02 sensors? as these can affect mixtures at cruze. mine also pours black smoke under hard accleration and i also get the biuld up of black gunk all over the rear or the car, im thinking we are not alone , lol

[shredder667]

yeah, noticed a couple around canberra with black rears. shoulda bought a black car.

[Betz]

I find with my GTR that when the oil is fresh and i have cleaned my pods I have a pretty clean rear bumper, after about 3,000 k's she gets that black beltching crap all over the place.

I do my service at maximum 5,000k intervals and it real makes a difference

btw my ar is the same 12.5

[shredder667]

cool, well i was considering getting a new intake system so i'll see how that goes, cheers!

[R31Nismoid]

could be a fuel reg failing?

could be a dead cat convertor

lots of things

[shredder667]

yeah, was also thinking cat converter. i'll just put up with it for the time being i guess. there's a special on some gt-ss's that require my wallet's attention first! thanks guys!

[cuppas]

12.5 is not mega rich

isnt the ideal 12.0 or thereabouts?

[Rav]

If it's only when you are makeing boost most likely just boost smoke. And GTR's blow alot smoke normaly anyway.