E85

[swathdiver]

Just curious @swathdiver , have you ever done a comparison of mileage while on the highway with windows down, compared to windows up? I've always wondered how much of a difference that would make, say driving 70-75 mph.

No, too hot, too noisy and not enough expendable income! I did that test though during city driving with the '85 and '86 GNs, 16 mpg AC on and 18 mpg AC off.

I have sometimes seen a mileage increase when putting the transfer case into AUTO while at highway speeds though.

 

[Tonyrodz]

No, too hot, too noisy and not enough expendable income! I did that test though during city driving with the '85 and '86 GNs, 16 mpg AC on and 18 mpg AC off.

I have sometimes seen a mileage increase when putting the transfer case into AUTO while at highway speeds though.

With my work van, on the highway, I don't know if it's better to run with windows down or ac on and windows up. Gas is just so expensive, and I'm mobile.

 

[swathdiver]

With my work van, on the highway, I don't know if it's better to run with windows down or ac on and windows up. Gas is just so expensive, and I'm mobile.

Run the AC and use high test. I was running a delivery route some years ago with one of our Pontiacs. 3AM to 3PM never turning off the motor. I would get 12 mpg running Sunoco or a little more on Mobil 93 back then. Boss implored me to run 87 and so I did, one tank of Mobil's 87 and got 8 mpg. Lesson learned.

You're getting old like the rest of us, the AC keeps us cool, helps us dry out after sweating/working, is not so tiring as no AC, etc. The benefits far outweigh the mpg increase. Just the cost of doing business.

 

[kbuskill]

I have the torque pro. I think you may need to pay the $5 or whatever it costs to get more PIDsView attachment 200978

Ok so I finally figured out the proper PID parameters to show the ethanol content on my 2008.. it was as follows...


@LanceD

Since you appear to have the Oil Pressure and Oil Temperature gauges working would you mind posting up those PID parameters that you are using for your truck?

Also if you have the Transmission Temperature working that would be great also.

 

[swathdiver]

I'm on my 4th consecutive tank of E85 and the alcohol content has reached 78%. During the winter we ran 7 tanks of E85 in a row and started with 52% and ended the last two on 71%. Two different stations, across the street from one another and both say the fuel is not their brand, ie not Racetrac nor Sunoco. Shell on the Turnpike says the same thing.

 

[kbuskill]

I'm on my 4th consecutive tank of E85 and the alcohol content has reached 78%. During the winter we ran 7 tanks of E85 in a row and started with 52% and ended the last two on 71%. Two different stations, across the street from one another and both say the fuel is not their brand, ie not Racetrac nor Sunoco. Shell on the Turnpike says the same thing.

I don't have that many options... lol

I noticed while idling that my AFR commanded was like 9.76 : 1 I guess that is do to the E85 and that 89 octane wouldn't be so rich... but that is just a guess on my part.

I also noticed my cat temperatures were about 550° on both sides... I don't have any idea what they should be... just an observation.

I also saw the long term and short term fuel trims but again don't really know what any of that is supposed to be.

Any ideas on any of that James?

 

[swathdiver]

My STFT and LTFT move around all over the place. They generally come back to zero though, depends on throttle and speed. Hi negative at idle LTFT is usually a sign of a vacuum leak.

@Scottydoggs has a better understanding of fuel trims than I. Usually get it wrong and he corrects me!

I never paid attention to the AFR or cat temps, I can look later when we run the truck again.

 

[kbuskill]

My STFT and LTFT move around all over the place. They generally come back to zero though, depends on throttle and speed. Hi negative at idle LTFT is usually a sign of a vacuum leak.

@Scottydoggs has a better understanding of fuel trims than I. Usually get it wrong and he corrects me!

I never paid attention to the AFR or cat temps, I can look later when we run the truck again.

I was just looking at the data with the truck up to operating temperature and idling... I haven't looked at it while driving... I was just kinda curious as to what they are "supposed" to be and what affect the E85 might have on the cat temperatures compared to 89.

Maybe some difference... maybe none... it was just a thought that crossed my mind when I saw it... lol

 

[swathdiver]

I remember that E85 set off the trouble codes for the more often than when on gasoline. I'll see if I can set up a log for the temps, LTFT and AFR later during an errand.

 

[swathdiver]

I don't have that many options... lol

I noticed while idling that my AFR commanded was like 9.76 : 1 I guess that is do to the E85 and that 89 octane wouldn't be so rich... but that is just a guess on my part.

I also noticed my cat temperatures were about 550° on both sides... I don't have any idea what they should be... just an observation.

I also saw the long term and short term fuel trims but again don't really know what any of that is supposed to be.

Any ideas on any of that James?

Idled for about an hour or so tonight after a 20 minute drive. Near the end of the idle time the outside air temp was about 79 degrees. The cats were both at 789 degrees. The LTFT were -3% and -5%. The AFR showed 1:1 and didn't move. That's not right now that I think about it. Will have to look for it somewhere else in the Tech2. Mileage went from 11.8 to 11.2 mpg.

I do notice that the Fuel Trims are in the negative more on E85 than gasoline.