Hello! recently i have noticed that on wot it comes black smoke......does this mean that i´m running rich on wot? otherwise the car runs great!

I have mafends on the car and a maftranslator...... the translator is set to 10% rich on the maf base and 4% on maf wot.
Could this be the, case? if i redused the wot to 2% maybee

Hello! recently i have noticed that on wot it comes black smoke......

mods: cutout, lid, mafends,afpr, maftranslator

 

Do you see just a quick puff of black smoke, or constant black smoke during WOT?

 

quick puff!

 

You might be running rich. Find someone with a wideband O2 and check it out. At WOT, I only had to increase my MAF 6%...and that's with a super sucker ram air scoop, lid, no cats, and catback.

 

Your running a little rich at cruise.

 

so what should i do?

turn down the maf base?

 

At the moment a dont have anything to scan the car with, but went on with turning down the maf base to 5% rich from 10% rich. Car runs fine.

Can you tell if you are running lean, because the car runs just fine now!

 

You can always pull your plugs to get an idea of where the mixture is, but the most effective way is to use a wideband or sniffer.

 

is there no other way to tell if you run lean? So i could be running around real lean and the car just seems to run ok??

 

During cruising situations, you can't really run lean unless you're off by more than 25% (which will trigger an SES light). You need someone to log your fuel trims for the bottom part of the MAF curve. That will tell you if you're running rich or lean. Products that can do this are things like a Predator, AutoTap, HPTuners, EFILive, etc. For WOT, you need access to a wideband O2 sensor....period. An LC-1 with a guage or an LM-1 will run you a couple hunder US dollars. Or, you can find a tuner shop with a dyno and they can help you dial in your AFR. Running aftermarket MAF ends is going to lean you out some. But, not to the point of being dangerous. The computer will compensate for an absence of fuel. The problem with that is if it ups your fuel trims to a positive number, it will dump in excess fuel at WOT and you will lose power.

 

Thanx for a good reply!

I no i need to scan the car. Hard to get hold of stuff in sweden, even harder is to find a shop that will tune a Ls1!