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Hey Guys,

I've noticed that my car is running very very rich at the moment. You get a pretty strong smell in the cabin, and the other day when my wife was driving infront of me, every time she gave it a hit, I could smell the fuel in her car about 20-30 meters behind. Under hard acceleration black smoke comes from the exhaust, and I also get a pretty bad misfire under heavy loads high in the rev range.

Anyone have any ideas? Are the misfire and rich fuel mixture related?

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NISMO,

The car running rich and misfiring are related. Have you wound the boost up recently? When you do this and don't have aftermarket management then the car will run very rich at about 5-7000rpm.

It would also be worth regapping your plugs down to .7mm, this should stop it misfiring as badly. You will possibly need an S-AFC to control the air/fuel ratio, and you can lean it out towards higher revs.

If you haven't adjusted the boost then the most likely cause is the AFM, just see if you can borrow someone elses for a few hours to see if there is any difference.

See'ya:burnout:

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Hey Fella's,

Thanks for the reply's.

GTS-t VSPEC, sounds like your on the money. I've had the boost wound pretty high for quite a while now ( running 0.9 to 1 bar for over 12 months ). In the begining all was good, but it's progressively gotten worse. I think I'll wind the boost down first, see how I go, and if it's still ongoing I'll take for a squirt on a dyno.

The fact that running very rich is no good aside, the thing sounds awesome. Changing gears high in the rev range gives massive backfires making it sound like a rally car going through the gears at full throttle. Scares a few pedestrians as well. :)

Cheers

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https://www.sau.com.au/forums/topic/8074-running-very-rich/#findComment-117866
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NISMO,

It's not that running the higher boost is bad but the factory computer overcompensates, running a very rich and safe mixture. If you do want to run higher boost levels then purchase either an S-AFC or aftermarket management. That way you can lean off the mixture in a safe way, and you'll end up with more power.

See'ya :burnout:

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https://www.sau.com.au/forums/topic/8074-running-very-rich/#findComment-118075
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