Useless Information

[randeez]

Sure, you can mix it up for cost savings but would have to drive it and see how performance is affected. At a certain percentage, which I do not know, the computer shifts from gasoline tables to the Flex Fuel tables or maybe there's a table for each percentage of alcohol content? Don't know.

fyi
the ecm is always in the high octane table until is sees x amount of knock and it drops into the low octane tables...

by most measures it just spits out a ratio to gasoline to know how much fuel to spray to reach stoich, the engine would be just as happy and never know what fuel it's using if tuning stopped there. before i had the ff sensor installed i rarely saw anything more than 68-70% ethanol shown on the torquepro app. with the sensor installed i usually see 65-80% ethanol only shown over 80% a handful of times. the ecm determines ethanol content via the virtual sensor by watching fuel trims after a fill up. why thats important....

improved performance comes from additional modifier tables that mirror base tables, about all of them modify by a percentage of ethanol.
ie, to make it simple: base timing is 20*, ethanol modifier table will add a max of 10* of timing, if 60% ethanol than it adds 6*.... whatever cell youre in will now bring the timing to 26*. other tables for fuel enrichment modify only under wot conditions adding in more timing and fuel. there are 2,3,4, variable tables that take coolant temps, intake temps, engine load, ethanol etc to modify

 

[iamdub]

Thanks for the schooling, Randy.

 

[randeez]

knowledge is power

 

[swathdiver]

Sorry on the delay but here is a pic of the 88 gas I mentioned. Looks like it is just e85.View attachment 211271

Thanks Thomas, this slipped by me. It's not E85, it's E15 or 88. My local Sunoco and that Marathon/Pro-Energy station labeled it like E85. I thought they also had E30 but was wrong or they don't anymore.

Getting in the 11s driving around town. Will be towing for about 150 miles today but will be lightly loaded and will be taking the rig out onto the highway for the first time. That trip just might burn 18-20 gallons of fuel! LOL We shall see.

 

[swathdiver]

The run is done. Picked up my buddy's 14 foot utility trailer and headed north on US Hwy 1 averaging 40 mph or so until the last ten miles when the speed limit was 55 and lights few and far between. Transmission temp got up to 185 and then cooled down at 55. Drove in M5 the whole time.

Loaded up and headed west to I-95 and then headed back down south. It's breezy out today and the truck did not want to shift into 5th at any speed over 60 mph. So on the highway she was turning 3000 rpms @ 70 mph in 4th with the selector set for M5. The truck itself weighed around 6900 pounds and the trailer about 2800. Brakes were not working well on it this time, set gain all the way and could not get them to lock up when empty. Still stopped fine.

4th gear @ 70 mph the instant MPG showed 5 mpg burning E85! LOL At 65 it shot up to 6 MPG! LOL Slowing to 60 the transmission shifted into 5th finally and was turning about 2000 rpms, forgot the MPGs on that one but the transmission temp hit 192 as we hit our exit and hour or so later.



Gettin' better at backing up, nobody was run over and only had to make slight adjustments this time!

 

[swathdiver]

Something just didn't seem right about the brakes, specifically the trailer brakes. So I'd read and reread the manual, watched every youtube video on the subject and realized what a dummy I've been!

I've been hauling this thing around with no brakes! I was using the 4-pin to 7-pin adapter and it never dawned on me that this was ONLY good for lights! Duh! Duh! Duh! LOL

So after leaving the doctor's office I went out to the field where I parked the rig and swapped the adapter out and coiled up the 4-pin and plugged in the 7-pin. Lights all worked as before but now when I moved the slider on the brake controller, the little gain bars lit up! They didn't before.

Pulled out onto a sleepy road with no traffic and started setting the gain and got up to 7.5 and still couldn't get the brakes to lock up on the trailer. Trailer was empty too. At 7.5 and moving the slider it stopped real nice, even the truck without using the Yukon's brakes.

Darn, now I want to go out and tow again but was only a few miles away from my buddy's shop so I brought it over there and made a spectacle out of my trailer backing abilities and garnered the sympathies of the local mechanics who guided me in close enough and they picked the trailer up off the hitch and moved it into place right proper! LOL

I'm a slow learner and learn best by doing, not being told or being shown but by doing. Well, now I done it! LOL

I wanted to weigh it but we were too busy getting the house transformed into a home yesterday. Maybe next time.

 

[kbuskill]

Something just didn't seem right about the brakes, specifically the trailer brakes. So I'd read and reread the manual, watched every youtube video on the subject and realized what a dummy I've been!

I've been hauling this thing around with no brakes! I was using the 4-pin to 7-pin adapter and it never dawned on me that this was ONLY good for lights! Duh! Duh! Duh! LOL

So after leaving the doctor's office I went out to the field where I parked the rig and swapped the adapter out and coiled up the 4-pin and plugged in the 7-pin. Lights all worked as before but now when I moved the slider on the brake controller, the little gain bars lit up! They didn't before.

Pulled out onto a sleepy road with no traffic and started setting the gain and got up to 7.5 and still couldn't get the brakes to lock up on the trailer. Trailer was empty too. At 7.5 and moving the slider it stopped real nice, even the truck without using the Yukon's brakes.

Darn, now I want to go out and tow again but was only a few miles away from my buddy's shop so I brought it over there and made a spectacle out of my trailer backing abilities and garnered the sympathies of the local mechanics who guided me in close enough and they picked the trailer up off the hitch and moved it into place right proper! LOL

I'm a slow learner and learn best by doing, not being told or being shown but by doing. Well, now I done it! LOL

I wanted to weigh it but we were too busy getting the house transformed into a home yesterday. Maybe next time.

Here is a little cheat/trick, from a class A CDL holder, to help you back up a trailer.

Place your hand at the bottom, 6 o'clock position, of the wheel when backing. If you want your trailer to go toward the drivers side, move your hand toward that side. If you want your trailer to go toward the passenger side, move your hand toward that side.

A lot of people have trouble backup up in general and when you add a trailer they are totally lost... lol

 

[swathdiver]

Thanks Ken! I've been doing those "S" turns but sometimes get at such an angle that it doesn't matter which way I turn until the whole thing is pulled forward and straightened out some.

In today's case, I also have a building and a pole to contend with. Steering from the bottom of the wheel is much easier on my brain! LOL

 

[gooffeyguy]

Something just didn't seem right about the brakes, specifically the trailer brakes. So I'd read and reread the manual, watched every youtube video on the subject and realized what a dummy I've been!

I've been hauling this thing around with no brakes! I was using the 4-pin to 7-pin adapter and it never dawned on me that this was ONLY good for lights! Duh! Duh! Duh! LOL

So after leaving the doctor's office I went out to the field where I parked the rig and swapped the adapter out and coiled up the 4-pin and plugged in the 7-pin. Lights all worked as before but now when I moved the slider on the brake controller, the little gain bars lit up! They didn't before.

Pulled out onto a sleepy road with no traffic and started setting the gain and got up to 7.5 and still couldn't get the brakes to lock up on the trailer. Trailer was empty too. At 7.5 and moving the slider it stopped real nice, even the truck without using the Yukon's brakes.

Darn, now I want to go out and tow again but was only a few miles away from my buddy's shop so I brought it over there and made a spectacle out of my trailer backing abilities and garnered the sympathies of the local mechanics who guided me in close enough and they picked the trailer up off the hitch and moved it into place right proper! LOL

I'm a slow learner and learn best by doing, not being told or being shown but by doing. Well, now I done it! LOL

I wanted to weigh it but we were too busy getting the house transformed into a home yesterday. Maybe next time.

So the trailer only had a 4 pin plug on it, even though it had electric brakes?

2001 Yukon SLT
2012 Yukon XL Denali
2011 Yukon Denali RIP 5/20/18

Sent from my SM-G930V using Tapatalk

 

[swathdiver]

So the trailer only had a 4 pin plug on it, even though it had electric brakes?

The trailer has both! My buddy told me to use the 4-pin so I listened and whipped out my GM adapter oblivious as I bet he is!