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Discussion Starter · #1 ·
i let my car warm up for some time every mornin. the exhaust is faced to my fence.
i had a look today and i found BLACK dots lightly splattered over the fence and even on the back of my car(maybe from deflecting off the fence and onto the rear of the car)

i started the car when the temp was hot outside and i saw no sign of oil or fuel splattering out of the exhaust. but the muffler seapage hole had black marks around it so i know it has been coming from my car.

is this stuff burned/unburned fuel? (my car runs rich)
when i touched the stuff it was kind of a chalky consistency.
i dont know if this is normal but it seems like it was a once off thing cause ive been checking every day now and hasnt happened again.

p.s. when i start the car is very cold weather, the exhaust smokes a greyish colour for a few minutes, but when i start it in cool to warm weather, no smoke at all.
 

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Could be that the carbon in your exhaust is becoming dislodged.

Have you changed any exhaust components recently?

Might be a good idea to have a look at your turbo. Pull off the intercooler pipes and have a look inside and run your finger in it to see if there is any oil (or a lot of in there)

Of course with engine off and at cold temp.

Smell the stuff that comes out. If it smells like fuel or oil, then problems

Regards

Zako
 

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Discussion Starter · #3 ·
Have you changed any exhaust components recently?
i got a new 2.5" cat-back exhaust about 1 month ago. but this black spalttering would have happened sometine in the past 2 weeks.

Smell the stuff that comes out. If it smells like fuel or oil, then problems
nope. it smells a little like rotten pubes if u smell it right up close due to my clogged CAT. :p but other than that u cant smell a thing.

should i rev the engine hard maybe to dislodge any remaining stuff in there?
 

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I say it's just some carbon coming loose with the extra air flow coming outta it.

Just take it for one hell of a thrash! It doesn't sound too major

Oh and rotten pubes?? My friend, what have you been smelling!

Regards

Zako:rolleyes:
 

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Discussion Starter · #5 ·
Oh and rotten pubes?? My friend, what have you been smelling!
hahaha....as i said earlier...uni is finished for the year and its partay time for the whole summer hahaha ;)

p.s. craig tells me that it is just fuel. so ill go by that :D
 

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It's unburnt fuel. My gate has a black line across it from my FJ40's side exhaust when I was running a 4 barrel holley (untuned). I painted the same black line on parked cars when I drove into a carpark. After rejetting it the black graffiti stopped. It's fuel.

When are you going to get your car tuned duckhead ;)
I can't think of a problem you've posted that hasn't been fuel related, except you VCG. :)
 

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yes a little more time getting your car tuned by a professional and less time smelling old granmas pubic regions could help your car :p

i don't know what type of performance you'd get if its running this rich. It wouldn't cost too much to get a tune (and a dyno readout while your there!) and you might find it will fix your other problems.
 

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Discussion Starter · #9 · (Edited)
yeah well unfortunately ive been working 45 hour weeks lately since the end of uni and just havent had time.

if there is some sort of vacuum leak somewhere, then i get it tuned...will it return to being rich straight away?

p.s. is ultratune the only place to get cars tuned here in sydney? cause ultratune really are a ripoff.
 

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ducktape69 said:


if there is some sort of vacuum leak somewhere, then i get it tuned...will it return to being rich straight away?

No, they should be able to locate the problem. They couldn't tune it with a vacuum leak.
 

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Discussion Starter · #11 ·
aight ive booked the car in for wednesday at ultratune $150.

since i havent got round to fixing the dissy seal and valve cover gasket yet...could the leaking dissy seal(oil in the dissy cap) be causing this such bad richness?
 

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Oil's not a great conductor but I've never had oil in a dizzy so I wouldn't know for sure.

You've got me excited about your tune. It will be interesting to find out what's been causing the drama. I think (just a guess) they'll find a problem in the setting of your BOV.
Whatever it is will probably help someone with the same problem.
 

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Discussion Starter · #13 ·
yeah hehe...hwo do they actually TUNE it?
do they change ECU settings? or do they physically change parts that they see are bad after putting it on a dyno?
 

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thay will check your codes, set timing to factory specs, check for vaccum leaks and maybe a exhaust emmision analysis
dont expect much difference
 

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grumtax said:
thay will check your codes, set timing to factory specs, check for vaccum leaks and maybe a exhaust emmision analysis
dont expect much difference

Unless of course, you hade a faulty sensor, bad timing, a vacuum leak you could stick your fist in & a clogged cat! Then you'll notice a fair difference.

I think Grumtax meant to say, if your car is running well you won't notice much difference. I think we can assume Ducktape has a fueling issue.
 

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my 626 had all the same problems as his, it had a 3 inch dump of the magnaflow so my driveway was black i just assume its what happens to these cars with bov's and big exhusts.
mine had a feul cut defender also wich is supposed to lean it out apparently
the car still put down 99kw at the treads and ran like a dream
 

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How about something simple like runs rich only when started cold due to 'choke setting' being on, and condesation in exhaust. Thats my problem, and i think may only be your problem too. For the exhuast to be using fuel to coat walls with, wouldnt the fuel ignite inside the zorst, or even cause flamage outta the zorst? So i think, on simple terms, water and choke ruichness is your problem. It doesnt show on standard zorst's, because of how restrictive they are.
Duckhead, ive read some of your post's mate.. your an interesting chap. If you want, i'll let you try and beat my r32.. and, there is no difference between an r33 and 34...
and wrx's for my little 6 is no problem. catback, 10psi and im laughing. there not that quick from rolling.
 

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Discussion Starter · #18 ·
well the whole beauty of the rex is that it is AWD...so u cant say "oh its not that good from a rolling start" lol

and i know r32-r34 are same but basically r34's ive driven seem to be in spectacular condition basically due to their low KM's.

and about my issue...i doubt it is only at startup that its running rich or my car wouldnt be having this such bad fuel economy. im leaning more towards some sort of vacuum leak somewhere that is getting bigger over time. during the past week when i have boosted it, it boosts nicely to around 4000rpm, then after 4000rpm, there is no more acceleration after that. it normally continues to boost till around 5500rpm(i.e. i think a vacuum leak somewhere is opening under boost)

either way, i hope the tune solves the fuelling issue ... but even then i will still have a clogged CAT for the time being but oh well :p
 

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Discussion Starter · #19 ·
thay will check your codes, set timing to factory specs, check for vaccum leaks and maybe a exhaust emmision analysis
dont they tune the AFM also? and when they tune it...is it a permanant change or will the ECU go back to rich AFM?
 

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Hey duck.. what course are you doing in uni? im assuming your in uni? (Seems everybody into this new fandangled thing).

Also, there is a big difference between standing start, and rolling start.
 
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