ScanGauge/Economy Questions

[jrtcbmw]

Ok so have been noticing my truck has been getting pretty bad fuel mileage. like 9.8-10.5 mpg the last 5-6 tank fulls. I know winter fuel SUCKS!!! and have been told that a 2-3 mpg drop is normal, but my summer mileage was up in the 15-16mpgs.

So I figured it was maybe the fuel I was using, so I changed stations, i havent filled up since, but half tank in, i got a hold of the ScanGauge2. ive hooked it up and one of the settings is is GPH. at idle in gear its up 0.80-1.02, where when its in neutral is down around 0.50-0.60. Now i dont know if thats good or bad, thats question 1.

my other question is what can be causing such bad fuel mileage. I have good oil in there fresh motorcraft oil/fuel filters. The truck is a 2004 f250 with 70k on the clock and with a 4 mbrp tbe and sct tuner with SRL tune on it. also the truck has 33x11.5r17s (fuel mileage dropped maybe 0.5mpg after the rims/tires when on). I really havent driven the truck hard, other then the once in a blue moon full throttle run to clear out and stretch the trucks legs.

I hooked up my AE, looked at all the sensor readings, nothing really stands out but my FICM is reading at 47.5volts at idle and then while driving is drops down to maybe 46v. I have no driveablity issues, truck start like a champ every morning. Being a ASM at a Ford dealership and having years as a technician, ive seen all the signs and issues with 6.0s.

The problem is this truck/platform is all new to me, ive owned the truck for 7 months, so im learning more and more everyday. being at the dealership helps but, im just looking for other insight.

If more information is needed or anything along those lines please let me know. and trust me ive been using the search button a lot (work has been nice a slow with all the "worst storms of the seasons" that has hit my area )

Thank you in advanced
Jason

[mmandley]

going to help Bump this thread for you.

Im not sure what the issue it eighter but i can say when the truck is under OP temp its milage suffers alot.

Generaly speaking 1 gallon an hour is normal for V8 engines gas and diesel.

I would start with a new T stat only 20 bucks and 30 minutes of your time. Its 2 10mm bolts.

I have been flushing mine to get the old coolant out and running with no T stat to make the flushes go faster and all i got on the highway was 13 and thats what i get in town and the entire time the truck was in cold mode so it runs rich and gets less milage.

[caissiel]

The scangauge will have to be calibrated if you use a program file. It is off by as much as 43% on my truck on some settings. I will fill up and Zero it in and drive about 1/2 Tank and refill and then calibrate to match fueling tank readings. You will have to be at the same tank and not an other fuel location because I found that not all tanks have the same readings. Advantage ScangaugeII.

My truck will show 16MPG and get better as the Coolant heats up. At 180F the MPG readings are still in the low 20's. And at full heated engine at 191F the MPG readings can be at 27 to 50 MPG. And that is at the same speed and level ground driving alone at around 45MPH. There is a big difference in MPG with coolant temperature on my truck. Using the scangauge have helped me a lot in Ecomoding with my truck also.

Even seeing average 36MPG on the local roads wil only average in the 20's because these trucks are heavy in stop and go traffic. On the highway with the program set at level 3 with the Max Energy programer I can keep close to 28MPG for long period of time and sometimes as economical as the Toyota Matrix riding at 70MPH. Better than a Cavalier at the same speed also as I have in the past.

Good luck with your research. I can talk all day with the results I have logged with the scangaugeII.

[pizza pig]

winter blend fuel kills mileage... but so does a cool running diesel...

replace your thermostat if you arent seeing 190* temps at operating teperature..

Theres a reason diesels wear winter front covers

I need to replace my thermostat badly i get 18 mpg mixed in the warmer months.. but lately 12-13 mpg and its killing me, i just dont have the time to do the swap out.

[jrtcbmw]

I have a new tstate sitting in my tool box just waiting for the restore/restore plus and elc to all get here before i swap it.

Im gonna try to block off the radiator. i forgot how much that affects mpgs. I remember doing that to my bmw last winter and get a big improvement in performance and mpgs.

Anyone know if a good front cover for the 04 front ends that doesnt need to drill or glue on the grill?

thank you again for everyones insight

very useful information

Jason

[jrtcbmw]

Ok so a little update. Filled up today. Got 11mpg on this last tank. topped off at 28.6 gallons. Not too happy with the mileage but its better. But i just started at new station, so im hoping it helps and at the last fill up was only a half tank.

I ended up putting some cardboard between the condenser and intercooler to help bring up the ect temps. Helped about 5-10degrees.

Did the whole "Fill Up" with the scan gauge. And now my GPH isnt right. At idle im getting like 2.5GPH. and under load it gets UP there, unlike before when it seemed normal at 1GPH at idle and kept under 20 under load same type of load. I really havent driven too much to comment on the fuel mileage readings im getting, so after a little ill get and update

Thank you again
Jason