Requested lambda/cruising fuel consumption

I recently received a tune through a very good tuner. The tune is amazing and car runs like a dream. But I cant leave good enough alone. I am currently tuned on e85 and go through a quarter tank of fuel cruising in 40 miles.
2010 C63 AMG

Here is what I cant figure out. Im used to ve tables but this is way different than what im used to adjusting. I can not get the commanded lambda to adjust. Heavy acceleration I can. I am trying to lean out cruise and very light throttle.


What tables do I access for closed loop cruise lambda. Base lambda correction only allows adjustment to Delta -273 and this is well above my current cruising delta.

You could try changing the stoich min and max to represent the cruise Lambda you want. Haven't tried this myself but it may work, worth a shot at least!

If that doesnt help, increase cruise timing a bit as well. That should also help.

Are you the guy that posted on C63 owners with the MEP Tune??

Yes I am.

I have 42-44 degrees of timing at cruise. It drives absolutely perfect at the moment. Just won?t react to changes different than a lambda value of 1.
At delta temps cool than -140(cruise/light throttle) I?m targeting 1.06 but even a value that lean won?t make it change.

I?ve only adjusted the max stoich value but didn?t change a thing.

I?ve noticed that once the engine oil temp hits full operating temp, my delta temps freezes at -69 but commanded lambda just sticks to what my tuner set.

If you change the max stoich you need to raise the min stoich as well so it target a smaller (leaner) range

Car is still commanding 1 all the time during idle and cruise.

I did not try to measure all this myself, I drove up to the service center and ordered diagnostics, because people there have a lot of experience and they can tell exactly what the problem is and can be eliminated on the spot

Try the lambda efficiency table

Some nuances should be taken into account when choosing a lambda. But, to get to the truth, you should remember about factors that directly affect fuel consumption — these are weather conditions, driving style, tire pressure, and their condition, as well as the technical condition of your car.
It would be best if you also kept in mind the following nuances:
First, our cars' fuel level indicators show only the approximate value of fuel in the tank. And we need values that are accurate to tenths of a liter.
Depending on the angle at which we look at the arrow, we can also conclude the different amounts of fuel www.cararac.com.
— The fuel level indicator will show the correct value only if the car is on a perfectly flat, horizontal surface, and this does not always happen.
— After filling the gas tank, many level indicators need time to adapt. Only after some time, they begin to show the correct value. Unfortunately, many car owners do not know about this.

Quote:

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Originally Posted by Averales

Some nuances should be taken into account when choosing a lambda. But, to get to the truth, you should remember about factors that directly affect fuel consumption — these are weather conditions, driving style, tire pressure, and their condition, as well as the technical condition of your car.
It would be best if you also kept in mind the following nuances:
First, our cars' fuel level indicators show only the approximate value of fuel in the tank. And we need values that are accurate to tenths of a liter.
Depending on the angle at which we look at the arrow, we can also conclude the different amounts of fuel www.cararac.com.
— The fuel level indicator will show the correct value only if the car is on a perfectly flat, horizontal surface, and this does not always happen.
— After filling the gas tank, many level indicators need time to adapt. Only after some time, they begin to show the correct value. Unfortunately, many car owners do not know about this.

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Thanks!