Sorry to confuse you. My lean-burn comments were basically a red herring because it would actually cause the opposite problem.....Anyway, you are not missing anything and your SG is working as well as possible, except for possible minor tweaking of speed and cutoff. I think Gary believed that Wayne would not have sent the SG to you with a 14.7% fuel calibration so he thought that something was wrong with his SG setup. Gary has, I think, brought the Fuel Cutoff number down and saw no significant increase in accuracy. Sounds like you are doing pretty good with the SG.

 

Your right, lowering fuel-cut did not lower the tank average that I could see. Also, I think 14.7 is to much fuel calibration and a red herring. Wayne is good, but not that good. At any rate as I kept adding to the number at a tank reset the SGII is way-off (+5mpg lower) for the first 20 miles or more with the Nav sys tank MPG. Slowly the SGII starts to fall in-line with 4% lower than the Nav sys. If someone had a 14.7% calibration they would send the SGII back to Ron for their money. I just know from slowly increasing the calibration what to expect from the SGII.

When I first got my '09 FEH my SGII was reading MPG much higher than the Nav sys thinking it was reading much lower than gas pumped. I was thinking I was getting 50mpg plus when I was really getting ~45mpg. Most all of us agree now that the '09 Nav sys reads ~4% high but I haven't heard anyone else is having to adjust their SGII with an '09 FEH.

GaryG

 

I've recently settled on 11.8 for my SGII fillup adjustment. For the last 3 tanks it's been very close to the actual fill (within .2). The SGII is reading closer now than it ever did on my 2007 FEH. I usually had fuel adj around 8 or 9 on it.

Here is the data for my last 6 tanks. Sorry about the formatting. I'm not sure how to paste data from a spreadsheet into this post and have it show the column spacing correctly.

MPG(Fillup),SGAve,DashAve,SGAdj,MilesDriven
32.4, 32.0, 33.5, 14.7, 324.8
33.4, 33.1, 34.4, 13.7, 410.1
35.2, 34.8, 36.1, 12.8, 360.3
36.2, 36.4, 37.5, 11.8, 386.1
34.9, 34.8, 36.0, 11.8, 367.8
38.7, 38.5, 39.5, 11.8, 398.8

My Fuel cutoff is currently set at 18 (tps).

-- Rick

 

Hi Rick

There is a thread here where myself and one other '09 FEH owner came up with the average the Nav sys was off over 7 fills and come up with 4% high. I think your dash reading is most likely 4% high also. My SGII in my '05 FEH never had a tank adjustment and it was right On with the amount of gas pumped every time. I knew when I added gas if I got a short fill or a high fill into the vapor space based on all the gauges in my '05 FEH. The MTE gauge is one of the best gauges to determine if you had a short or high fill if you know the remaining fuel in the tank at 0 MTE. What I'm saying is each fill-up is a crap shoot for determining MPG unless you know for sure exactly how much fuel is in the tank before the fill-up. The gas you add to the tank over time divided by the miles traveled will give you your lifetime average but changing your fuel calibration is very tricky and has to come from a known factor. The Nav tank reading and the dash reading on the '05 - '08 will never be a known factor because it drops data after about 200 miles. Our '09 FEH no longer drops data till we reset it I now know till at least 733 miles which is the longest I've travaled on a single tank. I've ran out of gas twice in my '09 and know I have .8 gallons left at 0 MTE so now I know based on my MTE from ~50 miles how much gas is a short or high fill and know the '09 FEH has a 1.6 gallon smaller tank capacity than my '05 FEH. I'm saying I could put about 17 gallons in my '05 from empty and about 15.4 gallons in my '09.

I don't try to fill either car to the top and can't unless I'm on the right angle of the pavement. This means all of my tank fill now are short for the most part. The SGII should be adjusted 4% lower than the '09 Nav tank because the NaV system is off consistently and so should the SGII after correctly adjusted.

GaryG

 

My 2005 Navi MPG is always higher than real.

In my Honda Insight, The Honda's MPG is always higher than real.

Are car makers trying to be deceptive and make the average person (95% of the public ) who does not track as closely as we do think they are getting more MPG than reality???