What would cause over run fuel cut to not work?

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Jon k
Super MS/Extra'er
Posts: 1256
Joined: Fri Oct 14, 2005 10:28 am

What would cause over run fuel cut to not work?

Post by Jon k »

I used to run just fuel control on my 24v BMW motor and when I turned over run on, i'd take my foot off the throttle and it'd peg lean for fuel cut. Now I am running fuel and spark, and i am not sure if I need to set something other than just over run up, but i noticed when decelling via no throttle, it was still hanging at like 12.5 - 13.0:1 afr.

Do I need an AFR target map or is there something else required for over run to work?
Jon k
Super MS/Extra'er
Posts: 1256
Joined: Fri Oct 14, 2005 10:28 am

Re: What would cause over run fuel cut to not work?

Post by Jon k »

Actually I figured it out - my negligence is the reason it doesn't work.

RPM Greater than: 1300 ok
and KPa lower than: 29 ok
and TPS lower than: 5 not ok


I remember my closed tps adc in calibration was like... 38 or so, but I forget exactly - I don't have my car here but i'd like to set up my MSQ so I can load it and go. Is there a file that the calibration is written to?
1992 BMW 525i M50 Non Vanos 24v Turbocharged
Stock COP Wasted Spark
MS2/E v3
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