Viper won t take fuel

[TexasTonka]

I've had this issue the first year of ownership on my 2015 TA2.0, the flap in the 'capless' filler neck does not allow the car to take fuel. Have to pull out the emergency funnel and force it open to slowly fill the tank. Was fixed under warranty and had not had much of an issue until today, car had been sitting for 8-10 months with engine out for some upgrades and now the filler neck is sticking on me again.
Is this common in the G5? Any home remedy to fix it instead of dealer fix?

Ideally I'd like to throw away this 'capless' design and throw a wide pipe conversion on it with a cap- no more issues, but that won't fit under the lid.

[finalleaf]

Curious, does it work if you just pull back the rubber part of the handle (near the nozzle)? My Viper won't fuel at all unless I'm holding it back and I've just been doing that as a workaround

[ViperGeorge]

Two suggestions. One, turn the gas nozzle 90-180 degrees. Some pumps seem overly sensitive. I had to do this at my local station until they changed their pumps. Now they work fine. Second, check the 1/2 plastic line that runs from the driver's side firewall under the fuse box. It is the line for the EVAP system. It tends to melt. If it melts open you can still fill the car, if it melts closed you can't. The one on my 2015 melted and I fixed it (and rerouted it further from the engine) with gas line. They can melt even on bone stock Vipers but if you have headers, it is sure to melt.

[GTS Dean]

Curious, does it work if you just pull back the rubber part of the handle (near the nozzle)? My Viper won't fuel at all unless I'm holding it back and I've just been doing that as a workaround
Fortunately, we don't have those prophylactics here.

[BSLSK]

Try pulling the nozzle back out about half an inch or so. I've also seen other owners have to rotate the nozzle 180 degrees, but I've never needed to do that.

[TexasTonka]

Curious, does it work if you just pull back the rubber part of the handle (near the nozzle)? My Viper won't fuel at all unless I'm holding it back and I've just been doing that as a workaround


Down here in Texas we don’t have those. I appreciate the advise, I did have to do that a few times when I drove across the US.

[TexasTonka]

Two suggestions. One, turn the gas nozzle 90-180 degrees. Some pumps seem overly sensitive. I had to do this at my local station until they changed their pumps. Now they work fine. Second, check the 1/2 plastic line that runs from the driver's side firewall under the fuse box. It is the line for the EVAP system. It tends to melt. If it melts open you can still fill the car, if it melts closed you can't. The one on my 2015 melted and I fixed it (and rerouted it further from the engine) with gas line. They can melt even on bone stock Vipers but if you have headers, it is sure to melt.


Try pulling the nozzle back out about half an inch or so. I've also seen other owners have to rotate the nozzle 180 degrees, but I've never needed to do that.

drove it 250+ miles, first two stations if I started it at 180* and slowly rotated to 90* it would take fuel, third fuel stop I nothing, had to take out the emergency funnel and use it to trickle fuel in to get home.
pleads me to belive it is the secondary flap inside the filler neck that is not opening correctly and allowing raw gas to splash back in the emission sensor of the fuel pump. It’s an issue if you ‘top off’ and let fuel sit on that flap so I think sitting for so long while engine was out let it corrode or get bunked up some how.

I’ll check the evap line too, lord knows a 9.0L with full headers and exhaust makes some heat.

[GTS Dean]

Kurt - If there is a second check valve down the neck, you might buy a 2 ft piece of nylon air brake line to probe down deep to loosen it up.

[TexasTonka]

Kurt - If there is a second check valve down the neck, you might buy a 2 ft piece of nylon air brake line to probe down deep to loosen it up.

There is a second check valve, unlocked with the emergency funnel and tricked it to stay unlocked by using a long screwdriver. Send down inspection scope to look at it and everything is free of gunk in both flaps and both open freely when pushed with end of scope. MAy not be the flap in the neck after all but possible build up pressure or some other nonsense going on.

I got a call from a Viper tech this afternoon on the subject and I'll be looking into his theory this coming week, apparently it was a fix on a few G5 that had similar symptoms.

I may be fabricating my own filler necks! LOL

[Toxic]

Hey Kurt,

I have the same problem with my 17. Turning the pump handle upside down is the only thing that solved it. Haven't replaced it yet. I had the same issue with a 2009. My '14 fills just fine.

[TKO MOTORSPORTS TEAM]

Not sure if this would help or not???. I was walking around shop and saw that we have a 5th gen viper fuel filler neck sitting on the shelf. If a few pics of the filler neck off the car would help diagnose problems just PM us and we will send some pics

[ViperGeorge]

Hey Kurt,

I have the same problem with my 17. Turning the pump handle upside down is the only thing that solved it. Haven't replaced it yet. I had the same issue with a 2009. My '14 fills just fine.

I believe the issue is more with the sensitivity of the pumps not the filler neck. Mine would act up at certain gas stations but not all. Once my local station changed their pumps no more issues. My wife's SRT Grand Cherokee had the same problem until the pumps were changed.

[GTS Dean]

The dispenser nozzles themselves have a backflow shutoff sensor in them. There are different suppliers and designs, but OPW company is one of the most prolific in the industry. They will usually have a small second channel inside the nozzle that senses backwash and immediately trips the dispenser handle out. As pointed out several times above, I've had to rotate the dispenser nozzle around in the filler neck to different positions to make sure the tank will fill.

If your tank vent hose is blocked in any way, the fuel will not be able to displace the vapor in the tank to allow liquid fuel flow. Some states have strict vapor recovery regulations. The dispenser nozzles will have the corrugated rubber device over the aluminum nozzle and another hose to the handle. This allows fuel vapors to be returned to the underground storage tank and not released to the atmosphere. There is a rollover check valve ball in the tank vent circuit, and another in the vapor recovery circuit to the engine. If either of these are stuck, you can have problems.

[TexasTonka]

Not sure if this would help or not???. I was walking around shop and saw that we have a 5th gen viper fuel filler neck sitting on the shelf. If a few pics of the filler neck off the car would help diagnose problems just PM us and we will send some pics
I appreciate it, have a new filler neck on order now.

[TexasTonka]

Hey Kurt,

I have the same problem with my 17. Turning the pump handle upside down is the only thing that solved it. Haven't replaced it yet. I had the same issue with a 2009. My '14 fills just fine.

Crazy how common this is across the entire range. Was so happy that my Wrangler showed up with a traditional spin on cap.

[TexasTonka]

I believe the issue is more with the sensitivity of the pumps not the filler neck. Mine would act up at certain gas stations but not all. Once my local station changed their pumps no more issues. My wife's SRT Grand Cherokee had the same problem until the pumps were changed.

Agreed. But there is also a design issue here as well. I’ve had the filler neck replaced under warranty on my Jeep SRT, Jeep Trackhawk and G5 viper. I’m sure it is all basically the same part.

[TexasTonka]

The dispenser nozzles themselves have a backflow shutoff sensor in them. There are different suppliers and designs, but OPW company is one of the most prolific in the industry. They will usually have a small second channel inside the nozzle that senses backwash and immediately trips the dispenser handle out. As pointed out several times above, I've had to rotate the dispenser nozzle around in the filler neck to different positions to make sure the tank will fill.

If your tank vent hose is blocked in any way, the fuel will not be able to displace the vapor in the tank to allow liquid fuel flow. Some states have strict vapor recovery regulations. The dispenser nozzles will have the corrugated rubber device over the aluminum nozzle and another hose to the handle. This allows fuel vapors to be returned to the underground storage tank and not released to the atmosphere. There is a rollover check valve ball in the tank vent circuit, and another in the vapor recovery circuit to the engine. If either of these are stuck, you can have problems.

Crossing fingers it is not the check valve in tank. Not going to cut open a carbon fiber body shell to free that. There is a vent pipe right off the filler neck. I’m suspecting that is the culprit since the flaps in the neck seem to open when looked at with scope.

Checked extended warranty and it is still covered so new neck is being ordered. We will pul it apart and investigate the issue in detail and report back what we find.

[ViperTony]

I don't remember what the part is called...but I believe there's a vent? line running by the drivers' side headers. I know of a G5 owner that had issues filling up his tank and it was due to a melted vent line by his headers. Replaced it and it was all good.