Yes, i understand you can be ol or cl in SD mode. I was talking OL/WOTOriginally Posted by foff667
dont fall into the trap even I fell into once thinking SD & OPEN LOOP are the same thing...you could be in SD closed loop or SD open loop, obviously if your in SD closed loop your not going to be running on the OPEN LOOP FUEL ADDER table
Correct, and this is why on boosted vehicles we tap a IAT sensor in the air stream seeing boosted air
The 12% discrepancy between commanded and actual has
to come either from the airflow side or the fuel side. The
VE tuning methods don't really separate the two but tune
to a result. This may give you perfectly calibrated airflow
readings, or it may give you airflow and fuel shot prediction
that are both wrong but compensate each other. Like the
advice several years ago was to jack the IFR table to get
fuel trims right, irrespective of whether the injectors were
wrong or not. Do this and then tune VE, you have a "two
wrongs make a right" situation.
If your MAF and VE-based airflows are fairly close in the
4000-5000RPM range then I would suspect it's not an
airflow-side problem.
If your AFR starts off matching OK in the midband but
falls away with RPM then look to fuel delivery - pressure
at the rails, duty cycle clipping, etc.
The enrichment rate sets how quickly you get to your selected enrichment value. From the scanner, if you log FA Mult you can see this value ramping up when you go into PE, and then ramping down when coming out of PE. Changing the enrichment rate affects the slope of these ramps.
Correct, in the ford world this is called open loop delay. You want the enrichment as fast as possible when going WOT
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