10.9 mpg? Is it bad?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

B-train

Full Access Member
Joined
Sep 12, 2022
Posts
1,932
Reaction score
3,222
The no dad says a lot and I'm sorry for you. Dad's are worth WAY more than this ****** society nowadays thinks......but that's a topic for another time.

You need some good financial, spiritual maybe, and some life direction I feel. I would like to nudge you to listen to some Dave Ramsey podcasts and see if anything rings a bell, or stirs something inside you. You will continue to live this hampster wheel to nowhere if you don't make some drastic changes, and I think listening to some of his stuff will help.

He's not a preacher or anything like that, just a guy who's been down to the bottom w/o $ and clawed his way back, but learned from his past mistakes and now wants to help others in the same predicament.

My wife and I did the plan and are debt free of everything and hope to retire early. It does work.
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
19,148
Reaction score
25,183
Location
Treasure Coast, Florida
Usually use e85 so I expect that from e85 but now I’ve been using 91 with no ethanol and I still get 10.9 mpg average. However, my instant economy is around 14-15 mpg on 91 when I’m just driving around town at say, 25mph.

Is this normal? Does it take a while to adjust back to other averages? My tire PSI is 40 in the back and 38 in the front if that’s any consolation,I have an exhaust leak so not sure if that cuaused worse mileage, and i was also gonna change the plugs and wires to see if that fixes it.

TLDR: still getting low average gas mileage after switching to premium gas.

A half tank of premium seems to last me barely 2 days.
It takes a couple of tanks to get the alcohol level down usually. However, low speed city driving is no friend of the mighty V8 engine. My Yukon XL with the 5.3 averages 12.7 MPG with 100% city driving (average speeds at or below 21.2 MPH) on 93 octane gas and 9.6 MPG on E85 with 100% city driving.

If you are interested, at your next fill up, record this data from your DIC and the gas pump:

Brand of Fuel
Grade of Fuel
Alcohol % (Do you have a scan tool?)
Fuel Pumped
Price per Gallon

Odometer
Trip Odometer (since last fill up)
Fuel Used (since last fill up)
Engine Hours (since last fill up)
Trip Time (since last fill up)
Average Fuel Economy (since last fill up)

With this data you can determine what your average economy is at differing speeds, cost to drive the truck per mile... all kinds of stuff.

I use it to show me which brands deliver the best mileage and remind myself that low octane fuels deliver less mileage.

Since a tank of gas can cover a myriad of driving conditions, we calculate for an average speed for that tank of gas and then with that data calculate what the average percent of city versus highway driving was done. Then use this data to show us what the gallons per hour was for that tank of gas which is really the best measure of our engines performance. This can also alert you to problems with the car if the efficiency begins to fall off.

Now you don't have to make these calculations every time mind you, you create a spreadsheet in excel for example and let the data compute each time you enter in the fuel stop data.

As for your broken exhaust manifold bolt, is there an exhaust leak because of it? Is the bolt head broken off flush with the exhaust manifold's flange?

Do you have an ODBII adapter and an app on your phone like Torque to view data? If so, you should set it up for checking your alcohol content to make sure you don't have problems with the O2 sensors making accurate computations.
 

BG1988

Full Access Member
Joined
Nov 14, 2018
Posts
2,946
Reaction score
1,344
Usually use e85 so I expect that from e85 but now I’ve been using 91 with no ethanol and I still get 10.9 mpg average. However, my instant economy is around 14-15 mpg on 91 when I’m just driving around town at say, 25mph.

Is this normal? Does it take a while to adjust back to other averages? My tire PSI is 40 in the back and 38 in the front if that’s any consolation,I have an exhaust leak so not sure if that cuaused worse mileage, and i was also gonna change the plugs and wires to see if that fixes it.

TLDR: still getting low average gas mileage after switching to premium gas.

A half tank of premium seems to last me barely 2 days.
dirty fuel injectors

that lowered my MPG quite a bit

Royal Purple Max-Clean 20 Ounce Fuel System Cleaner worked pretty well for me
 

BG1988

Full Access Member
Joined
Nov 14, 2018
Posts
2,946
Reaction score
1,344
Man. You got no idea how hard I work at balancing my time in my life. Some handle it better than other. Cudos to you.

I would love to fix my car. But I NEED to know how do it 100 percent. I can’t afford to try and fix something and ruin it in the process. I’ve said 100 times I don’t have the right tools. And yea my friends kinda suck. I know a few guys and they always have excuses for why they can’t help me or help loan some tools.

I’ve tried trading it. I had a 2011 CRV lined Up but dealer wanted me to pay $600 to replace the rotors bc they wobbled at high speeds on the test drive. They wouldn’t pay to fix it. They wanted me to.
I tried to trade for a 15 imapla at same place and they wanted $3000 down with a trade.

I have people offer to buy it. But it’s like than I’m without a car. And I need a car. And it would be really difficult to get another car. Bc they would want an absurd down payment I’m sure

I also tried to trade for a 2018 crv and they worked it with no down payment. But the car payment was $800 a month!
I net $2000 on a good month. I’ve honestly dug a deep hole in one bad purchase with this Tahoe it feels like.
yo udidn't dig a deep hole buying it just set aside 30-50 a month tell you saved up maybe cancel the cable for a few months and cut the starbux coffee

try and pick up an extra shift tell you have enough saved ... plenty of options but refusing to make the sacrifice....
 
Last edited:

j91z28d1

Full Access Member
Joined
Feb 28, 2022
Posts
1,982
Reaction score
2,289
Man. You got no idea how hard I work at balancing my time in my life. Some handle it better than other. Cudos to you.

I would love to fix my car. But I NEED to know how do it 100 percent. I can’t afford to try and fix something and ruin it in the process. I’ve said 100 times I don’t have the right tools. And yea my friends kinda suck. I know a few guys and they always have excuses for why they can’t help me or help loan some tools.

I’ve tried trading it. I had a 2011 CRV lined Up but dealer wanted me to pay $600 to replace the rotors bc they wobbled at high speeds on the test drive. They wouldn’t pay to fix it. They wanted me to.
I tried to trade for a 15 imapla at same place and they wanted $3000 down with a trade.

I have people offer to buy it. But it’s like than I’m without a car. And I need a car. And it would be really difficult to get another car. Bc they would want an absurd down payment I’m sure

I also tried to trade for a 2018 crv and they worked it with no down payment. But the car payment was $800 a month!
I net $2000 on a good month. I’ve honestly dug a deep hole in one bad purchase with this Tahoe it feels like.


sounds like you took what I said as a negative. it's not really, it's just what life is. life in general gets easier as you get older and earning potential goes up. and it's easier to fix something you enjoy. like I picked up a hybrid yukon. they are basically a cluster haha but it interests me, so I enjoy reading and learning stuff about it. plus our entire fleet is going electric, so it's kinda a cross over at work too, what I learn on mine puts me ahead of the other techs in the system that watch to much TV and hate something they don't understand. our electric stuff is much better suited to what we do with them and is showing it slowly after the growing pains of new delivery failures that everything has.


when I was young I was between cars, my s10 got totalled. insurance paid it off but left me without a car and zero cash. bummed 300$ and picked up a 91 thru a buddy. it was junk, like my girl at the time now wife wouldn't been seen in it. driver side window held up with a peice of wood. but it ran enough to get around. I slowly fixed things on it and ended up keeping it as a 3rd/4th beater car for years. finally sent it to the junk yard during covid. my wife threw a party all these years later. I was sad over it lol.

my buddy years ago got taken by a dealer on a newer car pretty badly, he was upside down like 8k. well he hit someone and totalled it, no gap insurance. left him carless and with bank wanting $8k. he had to get a personal loan for the 8k, I believe someone had to sign for him to get it. found him a old best up suby wagon for a few 100$. babied at along for about 3 years go get everything sorted.

stuff happens when you're young and poor. small things bite you eaiser.

I disagree with the dad being important. mine was an alcoholic and died when I was about 14. having a bad one is worse than not having one at all.. and honestly most humans are worthless crap, the odds if you getting one worth having is very low. count your blessings you didn't have to deal with a bad one, my life got so much better when it died.

I learned mechanic stuff because I hated construction work, and was to poor to buy anything nice. started with fixing bikes as a kid and kept taking cars apart till I figured stuff out, but horrible old Haines manuals to see pics. it wasn't like today where theirs 15 youtube videos showing step by step how to do everything. parts are more expensive these days but we also didn't worry about quality of said part, just called around to get the cheapest local thing. no Amazon haha. local parts stores and junk yards was kinda it.

we also didn't have the level of adhd everyone young has today from the technology world sucking the life out of you for clicks. so that helped. if something was broken, you literally had nothing to do but fix it. no other option.

so I see 2 options for you.. just drive the thing till it doesn't run anymore. change the oil often as you can to hopefully keep the afm from failing, maybe try to flush the tranny fluid but fluid is so expensive these days, it's probably not worth it. and then drive it into the ground while you just live your life. the less aggressive you. drive it, probably the better. which is boring when you're young. I feel like the tranny will be what takes it off the road.

unload it for a loss while you can buy the cheapest running junk you can find and drive that into the ground. maybe learn some basics along the way.
 

petethepug

Michael
Joined
May 4, 2016
Posts
2,446
Reaction score
2,465
Location
SoCal
It possible to have your BCM get stuck on e85 mode only seeing 90-100% alcohol in the tank. It can be reset with a Tech2 but not necessary since the e85 may be saving you some serious dough right now.

Food for thought. I just got the best mileage on a 200 mi trip because my wife drove our 09 Esky ESV AWD on e85. 11.1 mpg with four adults and luggage. Ave speed 70-75 in near 100* heat front & rear a/c blasting.

That’s with new injectors, o2 sensors, plugs, wires, fp & evap system. Research how to clean your MAF, check your plug gaps and leads at night for arcing or electrical leaks.

Use the e85 calculator below to see how far ahead you are running corn gas. You’ll need less frequent oil changes, run cooler and not get the carbon build up these motors are prone to. We save over $4k a year running happy hour fuel vs 91. My daughter shaves $25 bucks a tank vs Reg 89 in her 01 Chevy S10 x cab.


Here’s the data on the Esky. We’ve literally saved enough dough to pay the purchase price of the truck from e85.

5B3D06F5-7C2E-409C-80E4-2B23549F6324.jpeg
 
OP
OP
iboughtatahoe23

iboughtatahoe23

Full Access Member
Joined
Feb 17, 2023
Posts
663
Reaction score
365
It possible to have your BCM get stuck on e85 mode only seeing 90-100% alcohol in the tank. It can be reset with a Tech2 but not necessary since the e85 may be saving you some serious dough right now.

Food for thought. I just got the best mileage on a 200 mi trip because my wife drove our 09 Esky ESV AWD on e85. 11.1 mpg with four adults and luggage. Ave speed 70-75 in near 100* heat front & rear a/c blasting.

That’s with new injectors, o2 sensors, plugs, wires, fp & evap system. Research how to clean your MAF, check your plug gaps and leads at night for arcing or electrical leaks.

Use the e85 calculator below to see how far ahead you are running corn gas. You’ll need less frequent oil changes, run cooler and not get the carbon build up these motors are prone to. We save over $4k a year running happy hour fuel vs 91. My daughter shaves $25 bucks a tank vs Reg 89 in her 01 Chevy S10 x cab.


Here’s the data on the Esky. We’ve literally saved enough dough to pay the purchase price of the truck from e85.

View attachment 404434
Thanks for the info. So if it’s stuck, then is it just reading that? Or is it actually getting that to the gallon…?
 

Forum statistics

Threads
129,242
Posts
1,812,746
Members
92,348
Latest member
meandmyhoe20
Top