Author Topic: Black exhaust tip ?  (Read 1744 times)

Offline emery1990

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Black exhaust tip ?
« on: 28 April 2010, 16:53 »
I only recently polished my exhaust tip, it was like a brownish colour which id expect, but instead of going brownish again, its got quite a bit of black dust ( carbon presumably) Signs of incomplete combustion? is this due to the setup of the car , over fuelling perhaps. I am getting worried for no reason ?

Offline emery1990

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Re: Black exhaust tip ?
« Reply #1 on: 28 April 2010, 22:11 »
anyone?

seems weird as it wasnt black before i cleaned it off, now it is very black, ill get a pic up tomorow if that helps.

Offline sprout99

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Re: Black exhaust tip ?
« Reply #2 on: 29 April 2010, 08:07 »
i reckon your chrome has died.

I painted my last exhaust matt black which looked cool till it snapped. Now i have chrome again.
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Offline Andy!

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Re: Black exhaust tip ?
« Reply #3 on: 29 April 2010, 13:44 »
You may be worrying for no reason, however, this may also point to a more serious problem. Maybe valve stem seals or something along those lines. Does your car smoke at all?

Offline Neo Badness

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Re: Black exhaust tip ?
« Reply #4 on: 29 April 2010, 14:27 »
Are you getting crap fuel economy too? Could be running super rich perhaps?

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Offline emery1990

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Re: Black exhaust tip ?
« Reply #5 on: 29 April 2010, 17:19 »
No the car doesnt smoke at all? Erm only had it a week so cant comment on what the fuels like. The fuel gauge is crap and cant really tell when exactly i last filled up. But when i got it i put £15 of v-power in and that got me 100 miles, so doesnt sounds too bad. Oh thats another thing, no point starting a new thread about, as ive got a 2.0l is it ok to use normal unleaded. For the 1.8 id understand, but heard somewhere if go bigger obn displacement you can sometimes use lower octane fuel as there isnt a chance of engine knock?

Also when i got it, my dads friend whos into his cars etc, said it smelt like it was running rich or lean, cant remeber what he said now!. Ill ask my mechanic when i sees him next.

Offline Neo Badness

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Re: Black exhaust tip ?
« Reply #6 on: 29 April 2010, 19:01 »
Sounds like it's running rich to me, not ideal but less serious than if it's running lean (can cause engine failure ultimately).
 Your Dads friend probs said it was running rich as you can't tell it's running lean by smell but it'll smell of petrol if it's running rich (incomplete combustion of the petrol in the exhaust gases thus petrol smell)

2ltr mk2 16v ? is this a 9a or ABF? running EFi or Kjet?

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Offline emery1990

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Re: Black exhaust tip ?
« Reply #7 on: 29 April 2010, 19:13 »
Thanks, yes you can smell petrol quite a bit. itd explain the black powder .

Sorry its a 9a with kr head 16v. Erm tbh im not sure, its an 88 plate if that helps think it may be k-jet. Would prefer not to pay 1.26 over 1.21!. But if its needed to get optimum performance, so be it.

Offline Neo Badness

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Re: Black exhaust tip ?
« Reply #8 on: 29 April 2010, 23:00 »
It'll be k-jet then my friend. Mechanical fuel injection, if it's running rich it's better than running lean as previously stated. However there is is an optimal balance of performance and economy. Some people swear by V-power as it has more detergents etc in it than say ASDA standard 97RON. Unless you have set the car up on V-power(99RON) or higher octane fuel you won't be getting the maximum performance as there is no fancy ecu brain making adjustments for the higher octane fuel. Without going into it too much higher octane = bigger bang= more power.

To summerise unless you setup your car and only run it on Vpower etc you will see negligible performance gain vs say someone in a brand new Scooby Turbo where the quality of fuel is far more important.

Run it on what you can afford and treat it to Vpower if it's been a good little golf once in a while:wink:

You don't own a Mk2, you support it.