Hi, I’m in the process of tuning my R53 mini on an EMU Black. I’m using V3 software and I’ve found that if the car is allowed to idle for a long time it gradually goes lean. Sometimes as much as 20% lean. Right now it’s pretty cold out where I live, around -5C. I believe this is due to the sensor g…

Can u post a pictur where the sensor exactly is mounted. Beside a complex model, there is no real SW solution for a heat soaked sensor. The real solution is to move the sensor further away from the manifold or any metal parts. With SW u judt can di bad workarounds…it is actually an HW issue. Had …

Yes, the sensor is stock location and is a TMAP so it’s giving both pressure and temperature. It’s bolted into the aluminum intake manifold. The issue is that there isn’t really a place to put it that isn’t metal. The whole intake after the supercharger is metal. I don’t know how it’s corrected i…

[image] Disabling perfect gas law GENERAL Hello ! ECUMASTER like most other ecu’s calculates injection time including Intake Air Temperature. The problem is it alters fuel injection time invisibly because of the ideal gas law (like every other ECU) because of t…

I have made the table -5 to 70C in 5C increaments and i add almost 10% fuel at 60celsius with the 20-30c being the 0% island. Since there is no way to disable IAT ideal Gas Law correction, because its in the algorithm of fuel caclulations. You can see how much IAT is ifluencing your situation by unp…

[image] junits15: R53 mini As discussed in the thread, this is no solution. It will improve ur situation, but at cost of accuracy in fueling in any other situation. IAT is a relevant value for airmass calculation. Without, VE won’t make sense anymore. But if u want to do it, u can set iat s…

I disagree that it can’t be fixed, this is the OEM sensor location so that means BMW has some kind of solution for this issue on the stock ECU. Weather or not the EMU can mimics that is a different story, it may not be easily possible to fix it on this ECU. We’re not looking to break the ideal gas …

I have the same problem. I think it can be fixed with a compensation map when the speed is closer to 0, using a delta value based on outside temperature and intake temperature, to fix fueling for heat soak, starting, and idle issues.

This is what I did, a correction table that adds injector PW when we are in idle and IAT is high. This works ok but as soon as you start moving the issue immediately comes back. Will need to consider other options to make it work better but its not half bad. [image] [image] [image]

honestly i think it may be better to just allow the STFT to take care of it, because the problem with my method is that the correction is only applied when at idle. As soon as you start moving the correction is immediately removed which causes the mixture to go lean faster than the STFT can react. …

I came across this issue 5 years ago on my R53. I made a custom correction table that activates based on vehicle speed with certain delays. I can post my settings if you’re interested? The other (expensive) option is to fit the TPE plastic manifold which I imagine would solve the issue.

R53 mini lean after long idle

EMU BLACK / CLASSIC

junits15 December 26, 2025, 6:15pm 4

This could work

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R53 mini lean after long idle

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