I own a 2013 Suburban 2WD, 5.3, Automatic, LT, 195,xxx mile.

I found I had a problem by accident. I run E85 all the time $1.59/gal (Unl $2.49). I stopped at a local gas station and put a couple of gallons in of unleaded to get me to the E85 station. After about a mile the engine lost power, started backfiring thru the intake. The engine would not idle. Engine rpms would not go over 1,000. Engine light comes on. Engine has no power to move the truck. I put in 10 gals of E85 and after a few mins it started to run fine. I thought it might have been a fluke. After a few tanks of E85 I let the low fuel light come on and put in 4 gallons of Unl. The same thing happened. The code from Onstar are emission codes. P0171, P 0174, P015B.

I replaced all O2 Sensors. (2) AC Delco 213-4229 GM Original Equipment Heated Oxygen Sensor, (2) AC Delco 213-3866 GM Original Equipment Heated Oxygen Sensor. I replaced the MAP Sensor. I replaced all (8) Spark Plugs and wires.

I can still replicate the problem. According to the local dealer, parts store and internet there is no E85 (Alcohol sensor).

I will say this last time was a little different. I only put in 5 gals of E85 in the tank instead of 10 gals. The engine started to run better but not normally. After about 10 miles the engine lost power, started backfiring thru the intake. would not idle. The engine rpms would not go over 1,000. Engine light comes on. Engine has no power to move the truck. I put in the other 5 gals of E85 and it started to run correctly. After half of a tank the engine light goes off. The codes from Onstar are emission codes. P0171, P 0174, P015B.

Any ideas?

 

You should be able to put in any percentage up to 85 and the computer determines alcohol content and adjusts accordingly. There is no alcohol sensor. 3 gallons is the minimum recommended when switching fuels.

From the owner's manual: "It is best not to alternate repeatedly between gasoline and E85. If you do switch fuels, it is recommended that you add as much fuel as possible — do not add less than 11 L (3 gal) when refueling. You should drive the vehicle immediately after refueling for at least 11 km (7 mi) to allow the vehicle to adapt to the change in ethanol concentration."

 

That is great information. I will try that in a few days. I will drive it to less than 1/4 of a tank of e85 the fill up with unleaded and hope for the best.

Thank you for the reply. James

 

Hey OP, I'm curious, when you fill the tank of completely with E85, what would you estimate your mileage to be per tank compared to using unleaded?

I have a place near me that has 87 pure gas, but I can't really see a difference in mileage between pure gas and E10. But I just like to put pure gas from time to time.

 

it's it labeled E10 or may contain up to 10%? The gas around me is currently showing only 3% so the mpg difference is negligible.

 

I run E85 all the time, I get 300 miles per tank........ Did the math, no matter how you stack it up, E85 (1.89) is still cheaper to run than regular fuel now @ 3 bux+ per gallon


just my 2 cents

 

Not into dual fuel motors, but I would never buy a diesel motor in a light vehicle unless it was a pickup truck for towing. The MPG is close but gas stations are mid to high octane prices for diesel. Best place is a truck stop as the D/F volume sales is high there, thus most often cheaper. Particularly is they have lots of competition.