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Formula

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Hiya is there a forumla to correct the lambda? I need to know how much fuel to take out in the fuel table cell.

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There is a formula (and it's covered in several of the basic courses / webinars) -- however, you need to make sure you are at steady state with those values -- and I would be surprised that you could have 99 kPa at 1000 RPM. Are you sure your MAP sensor is reading correctly? If not, that would explain why the mixture is so rich,

Tell us more about where this log file was taken (what kind of car, ECU, wideband interface, etc), on the road, load bearing dyno, inertia dyno, or just free-reving / idling.

Come to think of it i may have a vaccum leak somewhere. Ill have a look. I just wish there was a sheet with all the formula’s. Instead of looking through every single course to find it.

VEMS ECU, lsu 4.2 wideband, vr6 big plenum intake manifold, on the road.

Here you go. Multiplier = MeasuredLambda / DesiredLambda. You can see that when you are just getting started, by setting the target Lambda to 1.0, then you just multiply your current fuel table value by the MeasuredLambda to get onto target.

Another shortcut while trying to get close, just use MeasuredLambda - DesiredLambda as the percentage of fuel to add or remove. For example, if you measured .85 Lambda and your target was .90 Lambda, .85 - .90 = -0.05, just remove 5% fuel and you will be close to the formula multiplier of .944

Not trying to be a pain, just didn't want you to remove 20% fuel, when you really had a bad sensor value.

Awesome thanks!!!

Yeah that confrims my math. I was like 20%, that cant be right. I found a crack on one of the welds on the manifold. Thanks again.