McLaren 720s: Auto Start Stop stopped working

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McLaren 720s: Auto Start Stop stopped working

Postby ivoivo72 » Sat Mar 28, 2026 5:55 pm

Hi, this is going to sound weird, but after my tuner disabled my cold start, my auto start stop stopped working. I don't care for it, I know it has bad implications for the engine and annoys the hell out of most, but I'm deadly curious why this happened and my tuner isn't too responsive to explain.

Could this have been done accidentally, due to some temperature thresholds for example? Or could he have used some pre-made script that disables both those things? I tried looking at it myself but the damos I have (for mp4-12c) almost doesn't include any parameters for auto start stop, and I went through NSKH (cat heating idle speed), BBKHAKT (operating conditions for cat heating) and multiple other maps relating idle speed with coolant temp, and I couldn't really figure out what he did. I have an original file but I don't think the auto offset calc worked (the file is 2mb, the original is 4mb) so that's useless. Btw I'm completely new to this so pardon my ignorance.

Please, if someone has good definitions for this file, I would be very grateful if you figure out 1) what he did to disable the cold start 2) could any of this have killed my auto start stop, or was it killed via a different parameter.

The file is here: https://limewire.com/d/yQjVE#W08pD0LLqZ - and the original is also uploaded

ivoivo72
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