Stalling After Fuel Up

[nfancera]

I've had an issue for a while with my car (2018 Fiesta ST) idling rough or stalling after fueling up. I've tried at different fuel levels (top up, from empty, half full) and it happens regardless. It only happens while idling, sometimes being rough and sometimes completely stalling. The issue goes away after a mile or two of driving.

Any thoughts?

 

[SteveS]

If you search the forum this issue has been thoroughly discussed numerous times. It has to do with the evaporative canister getting too much gas in it, especially if you top up when fueling. Sometimes it requires replacement of the canister to fix it. But the general consensus is to fill only until the auto shutoff stops and no more.

 

[XR650R]

Yup.
Also, welcome to the forum! You'll find it a friendly and helpful community of FiSTers.

 

[ronniec687]

Welcome to to the forum. Converting your evap harness to an early model ST will help too. Very easy to do and theres one for sale here for half price. Id grab it if I was you. https://www.fiestastforum.com/threads/2014-5-evap-harness-50-shipped-lower-48-states.31231/unread

I've had an issue for a while with my car (2018 Fiesta ST) idling rough or stalling after fueling up. I've tried at different fuel levels (top up, from empty, half full) and it happens regardless. It only happens while idling, sometimes being rough and sometimes completely stalling. The issue goes away after a mile or two of driving.

Any thoughts?

 

[nfancera]

Thanks guys, that's a huge help! This has been driving me nuts but is just a small enough nuisance that I haven't done anything to fix it.

 

[WannabeST]

As a temporary fix, fill up your gas and don't fill past when the auto shutoff clicks. Let the pump sit there for a few seconds, take this time to clean your windshield, check your oil, take out any trash. This helps with the issue.
There's a couple write ups on here about converting to the earlier gen system and it appears to be fairly simple. Or you can just do what I did and buy the purge valve from autozone for a couple bucks and buy a spare.

 

[Volumetrik]

Just to adjust your expectations, I have a 2014 and I still have this issue. I never overfill, but the first 10 mins after a fuel up always results in rough idle. Stalled the car a couple of times coming off a stop, but only happened about 4 times in the last 9 years.

 

[NOVA_Ranger]

My car has stumbled after filling up in the past and more recently it has started stalling after fill-ups. New valve/harness currently on the way from Whoosh, and that'll be going on soon. Swap it out and be done with it is my approach.

 

[nfancera]

I'll definitely have to look into the conversion. I've tried not overfilling to the point where I don't even wait until the pump clicks, just put in 8 or 9 gallons and leave it, but still the same issue. I appreciate the advice!

 

[NOVA_Ranger]

I'll definitely have to look into the conversion. I've tried not overfilling to the point where I don't even wait until the pump clicks, just put in 8 or 9 gallons and leave it, but still the same issue. I appreciate the advice!

I swapped out the harness since last post. Pretty easy to do, took maybe 20 minutes, and no more stumbling or stalling here after filling up.

One related question somebody might be able to answer for me. After installing the conversion-style harness on my '19, there is one fitting that is left unused. Is it necessary to cap that unused fitting? I rigged something up and did that, with no issues to date, but I'll need to figure out a cleaner and more permanent way to cap the unused fitting if it is necessary to do so.

 

[Akumu]

Been having this issue since I bought the car in 2019. (A 2016 it is) Now at 152k is doesn't stumble but straight stalls almost immediately at first press of a fill up (fill up until click or just adding 8-9 gallons) Then barely idles at 2nd press until I give it fuel and then it's fine for that entire tank of gas. It will still stumble, but never stall, a bit at a light, but that's nothing new. Perhaps the 8-20 degree temps don't help? Regardless all of the silly little suggestions like not overfilling, letting the pump stay in the nozzle for X minutes, pumping slower, etc etc etc etc have never done anything. Shit, replacing the ENTIRE EVAP SYSTEM (canister and hoses) has never done shit. (What a waste of money that was.) Annoying, but it's nearly the only issue I've had with this car other than a dead Low Pressure Fuel sensor.

 

[Intuit]

Ever get any codes? Changes from stock? Any past-due maintenance, such as plugs? Something else that is potentially unique about a fill up is, it's a warm start that occurs with only a few minutes of shutoff time. It might occur with only the warm start and no fill up. Vacuum leak, MAP/MAF sensor and/or failing idle control solenoid has also been known to cause warm engine stalls.

 

[ron@whoosh]

I swapped out the harness since last post. Pretty easy to do, took maybe 20 minutes, and no more stumbling or stalling here after filling up.

One related question somebody might be able to answer for me. After installing the conversion-style harness on my '19, there is one fitting that is left unused. Is it necessary to cap that unused fitting? I rigged something up and did that, with no issues to date, but I'll need to figure out a cleaner and more permanent way to cap the unused fitting if it is necessary to do so.

yes , an aftermarket induction hose will have only one evap port connection
https://whoosh-motorsports.myshopif...low-silicone-induction-hose-kit-free-shipping

 

[NOVA_Ranger]

yes , an aftermarket induction hose will have only one evap port connection
https://whoosh-motorsports.myshopif...low-silicone-induction-hose-kit-free-shipping

Thanks much. I just ordered one!

 

[NOVA_Ranger]

Thanks much. I just ordered one!

Arrived and installed in 5-10 minutes. Thanks again!