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Old 01-30-2012, 09:38 PM   #4 (permalink)
SentraSE-R's Avatar
Join Date: Jun 2009
Location: Bay Area, California
Posts: 1,485

Mean Green Toaster Machine - '06 Scion xB
Team Toyota
90 day: 48.92 mpg (US)
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By default, the SG cutoff setting is 24, which means the SG registers 9999 mpg any time your throttle position sensor is <24 and your engine is in open loop. That's amazingly unrealistic, since your cars likely aren't in deceleration fuel cutoff then. Your current settings are more realistic.

One of my cars idles at TPS 15, and the other 2 at TPS 11 (one of these doesn't have DFCO). So of the two with DFCO, I set SG cutoff on the first at 19, and the second at 15. (The one that doesn't have DFCO never enters open loop on deceleration, so the SG never thinks its in DFCO.)

Car 1 is/was my Sentra SE-R. It entered DFCO when decelerating (TPS <19) in gear with rpms >2500. That effectively meant DFCO didn't happen in 6th gear below 65 mph! When it did happen, I paid dearly for it. The SE-R stayed in open loop for the next 4 minutes, running a rich fuel mixture the whole time.

Car 2 is my Scion xB. It enters DFCO when decelerating (TPS <15) in gear with rpms >1500. That means DFCO happens in this car in 5th gear at any speed above 35 mph. Not only is it DFCO-friendly, it stays in efficient closed loop as soon as I kick it out of DFCO by pushing the gas pedal.

Give yourself some time to understand your SG. You haven't learned how it works yet, and you haven't calibrated it.

Boycotting Exxon since 1989, BP since 2010
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac? George Carlin
Mean Green Toaster Machine
49.5 mpg avg over 53,000 miles. 176% of '08 EPA
Best flat drive 94.5 mpg for 10.1 mi
Longest tank 1033 km (642 mi) on 10.56 gal = 60.8 mpg
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