backfire when below 1/4 tank

[thor452]

So this has been going on for as long as I have had this sled. 2017 ltx le. when I get down on fuel but not even to the point that the low fuel light comes on. ( not sure this sled has a low fuel light as I have never got that low) the sled starts surging on a steady throttle when going slow and when you hit it, it will pop and backfire. Also when on the grade and running 80+ mph it will fall on its face like someone shut off the fuel and then recover. only happens when somewhat low on fuel and when I fill up it goes away. has anyone else had this issue and if so have you found the problem/solution? Thanks in advance.

 

[PowderFalcon]

2 things you could check

1 - the vent tube coming out of your fuel tank. i have seen them get pinched when routed down below the motor. if you pull your secondary clutch off, you can see it through there.

2- do you have the updated gas line return elbow going into your tank? should be black. if it is red, you need to replace with the updated one... or drill it out 3/16".

 

[Crossfire12]

Or Hydromat

 

[thor452]

I will check tank vent. seems like many are reporting issues much like mine but mine is always remedied by getting gas. and it starts at about 1/4 tank strange??? Others don't seem to be fuel level related.

 

[Michael Potter]

I had the same thing last weekend. Low on fuel light was on. Sled started acting as if it was out of gas hesitation but no backfire. Gave it some more throttle hesitation went away finished the last 20 kms. Probably on fumes by the time I got to truck. Mine is a 2017 and only had this happen a few times. I’m going to check my vent but also thinking maybe water in fuel.

 

[jonlafon1]

Okay had this last trip! I really believe it’s water in gas. Mine was at about 1/4 tank. So here is the story. I leave in the am -22 temps. I get fill up and ride 100 miles or so and return to SAME gas station and they have no gas either premium or mid grade. The back fire and falling on its face happens 5 miles from filling up. So I stop and add half s can of octane boost. No issue for last five miles. I did not hammer it just cruised to gas station. End up going to another gas station down the road and fill with premium. Before fill up No knock light just no power and back fires if getting on gas. I only had this ONE other time in 6k miles. That time it was somewhat low on gas also. This is in upper Michigan. To me it’s moisture in gas as no knock light at all just falling on its face and backfired on throttle snaps.

 

[Michael Potter]

I’m going to run some Seafoam in the fuel for a bit.

 

[jonlafon1]

I like sea foam but not heard it’s great for removing water. Good fuel system cleaner for sure. I’m thinking iso propo. Not sure what’s best besides drawing fuel tank completely. Klotz octane boost claims to remove moisture. Maybe someone will chime in. Or post with something that works best for moisture in tank. I truly believe this is the issue on symptoms mentioned

 

[Yam4Strokin]

It's running out of fuel. The fuel return design is not keeping the "banana clip" that the fuel pump sits in full of fuel and it begins to starve for fuel. Call Ulmer and get a Precision EFI fuel upgrade kit, it moves the return so it fills the "banana clip" when it's returning, it'll fix your issue.