2012 se Stalling at red lights

[Handy Andy]

Take a look around the outlet of the tailpipe.

IT should be dark color - similar to "Kingsford charcoal" but not greasy - if greasy- the oil is getting sucked back into the motor - more than likely from the PCV valve.

Another area to check would be when you find the MAP sensor - mine is located here...



But also check the BREATHER hose, that comes off the valve cover to the Air Filter - it too uses a "sponge" to mop up and hold oil - but the little "cup" it rests in - inside the airbox itself - under the air filter media - also can get plugged.

IF this hose gets plugged, the only way the engine can get rid of any vapors is thru the PCV valve and can force leaks to appear around the valve cover and spark plugs are in a trough inside this cover - which can get oil fouled from the inundation of oil which then generates a near dead short for the spark to follow from the coil - the high voltage arc will follow thru into ground outside to the cylinder head versus firing in the spark plug and cylinder.

 

[Itswiggs]

This is a great thread with tons of info. I am having this issue at the moment. Intermittently. Right after I fuel up and at red lights. Great info to look into @Handy Andy

 

[LionsTooth]

It's common for Fiestas to stumble after a fill-up. Mine will do it if I don't "breathe" the tank a bit. Instead of just pulling to nozzle out right away, try just letting it sit for about 15 seconds or so after it shuts off. Then take the nozzle out slowly, so that the vapors can come out a bit. I usually push the nozzle in and out a few times just good measure. I do all that and it never stumbles.

Don't top up, either. That makes it happen, too.

 

[Handy Andy]

It's common for Fiestas to stumble after a fill-up. Mine will do it if I don't "breathe" the tank a bit. Instead of just pulling to nozzle out right away, try just letting it sit for about 15 seconds or so after it shuts off. Then take the nozzle out slowly, so that the vapors can come out a bit. I usually push the nozzle in and out a few times just good measure. I do all that and it never stumbles.

Don't top up, either. That makes it happen, too.

Especially with more of the Alcohol blends they add to the fuel.

​

The Fiesta - unless it's branded (that decal on the vehicle by it's "Stuck on" model branding) - as a Flex-Fuel vehicle - too full of a tank can send itself to the shop because of the fuel blend attempts to destroy the EVAP system by trying to trap vapors that wind up making a mess with how the system processes these newer blends.

They (those that sign the forms each year for the newer emission laws to take effect per states that do this...) are pushing more and more corn-based fuels into our tanks and thanking us for the tax income they provide.

IF you can - as you fill up - fill up with slightly less gallons of fuel (quicker-smaller amount of fuel fill) than to wait for the thing to shut off - doing it that way, or not as often leaving more time between fill-ups to dry out the system - leaves an air pocket to help the car start and keep the EVAP system seeing more vapors than the liquid parts of the blend - it "remembers to" pull fumes into the canister and instead it winds up plugging up it's air-passage lines trying to clear/purge it out.

To Add: (If anyone still reads these...)

• IF you fill too fast these days - the amount of detergents they use, generates a considerable amount of foam - thru the mixing of the liquid fuel and trapped fumes in the underground tanks to push more reclaimed vapors and fuel into the tanks - generates a considerable amount of foam. So,t if you fill up too fast - the smaller volume of tank to keep it in can push this foam and it's trapped liquid into the canister - that, after it dries out - "cakes" and traps even less vapors and won't pass as much air thru it (Making it harder to start)- at time goes on. Think of it this way - after a summer of overfills or foam trapping in that canister - you'll need to spend close to as much as $200 in a DIY hour spent in your garage trying to swap put canisters that are best left to let the professionals and their set of tools on those fittings.

Just an FYI....

 

[Itswiggs]

It's common for Fiestas to stumble after a fill-up. Mine will do it if I don't "breathe" the tank a bit. Instead of just pulling to nozzle out right away, try just letting it sit for about 15 seconds or so after it shuts off. Then take the nozzle out slowly, so that the vapors can come out a bit. I usually push the nozzle in and out a few times just good measure. I do all that and it never stumbles.

Don't top up, either. That makes it happen, too.

I’ll try that. Can’t top off anyway, I’ll spill fuel all over the ground of the gas station. Something with the cap less design I guess. Don’t ask me how I know. lol

 

[Itswiggs]

Especially with more of the Alcohol blends they add to the fuel.

View attachment 9627​

The Fiesta - unless it's branded (that decal on the vehicle by it's "Stuck on" model branding) - as a Flex-Fuel vehicle - too full of a tank can send itself to the shop because of the fuel blend attempts to destroy the EVAP system by trying to trap vapors that wind up making a mess with how the system processes these newer blends.

They (those that sign the forms each year for the newer emission laws to take effect per states that do this...) are pushing more and more corn-based fuels into our tanks and thanking us for the tax income they provide.

IF you can - as you fill up - fill up with slightly less gallons of fuel (quicker-smaller amount of fuel fill) than to wait for the thing to shut off - doing it that way, or not as often leaving more time between fill-ups to dry out the system - leaves an air pocket to help the car start and keep the EVAP system seeing more vapors than the liquid parts of the blend - it "remembers to" pull fumes into the canister and instead it winds up plugging up it's air-passage lines trying to clear/purge it out.

To Add: (If anyone still reads these...)

• IF you fill too fast these days - the amount of detergents they use, generates a considerable amount of foam - thru the mixing of the liquid fuel and trapped fumes in the underground tanks to push more reclaimed vapors and fuel into the tanks - generates a considerable amount of foam. So,t if you fill up too fast - the smaller volume of tank to keep it in can push this foam and it's trapped liquid into the canister - that, after it dries out - "cakes" and traps even less vapors and won't pass as much air thru it (Making it harder to start)- at time goes on. Think of it this way - after a summer of overfills or foam trapping in that canister - you'll need to spend close to as much as $200 in a DIY hour spent in your garage trying to swap put canisters that are best left to let the professionals and their set of tools on those fittings.

Just an FYI....

Interesting. I completely wrecked out that fiesta I bought for the engine/transmission swap and when getting to the fuel tank and canister stuff In the back this info makes a lot more sense actually being able to see it physically. Thank you for all the info. You must work on these cars so much to know all this about them. It’s great

 

[Handy Andy]

As a driver I've seen a lot of service shops dealing with overfill and poor canister designs from earlier years - and even warranty work due to the issues of changing fuel blends to more and more alcohol per volume to petrol - it works like a water-softener - even on newer cars.