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Wonky gas gauge - Related to rough idle after fueling???

FiSTerMr

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#1
As most of you have had I got that rough idle right after gassing up. Lately it has gotten worse, none of the tricks work.

But what I notice now is that after fill up, the gas gauge gets inaccurate. I can go for a ride for 40 mi and the gas gauge will move. But when I get back in the car the next day, it's on full again, and the 'miles to empty' goes back up. I noticed it'll do that once and then start working again. It's happened twice so far.

Was wondering if anybody else had this problem... I think it's related to the rough idle gas vapor canister deal.

I plan on going to the dealer and getting it looked at. the only problem is it would be hard for them to replicate, because the situation has to be exact. I'm going to film it next time and bring it in with me.

I usually find that going to the dealer has a huge waste of time. Although, to be honest I've never been to the dealer with this car, thankfully. So Ford might be better than the experiences I had with Dodge and Subaru [emoji1696]

2017 w/Recaros - bone stock
 


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FiSTerMr

FiSTerMr

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Thread Starter #3
I get the rough idle as well when I'm refueling with the motor running but it's just temporary.
Yes, it's a long time issue for just about all of us. But now I believe it's affecting the gas gauge.

2017 w/Recaros - bone stock
 


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FiSTerMr

FiSTerMr

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Thread Starter #5
Did you park on a incline/decline?


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My parking space is at a slight incline. Nothing drastic.

2017 w/Recaros - bone stock
 


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#6
Do you have a gas cap or using the capless? I'm wondering if it might be sucking air in and causing it .I have a locking gas cap on mine and have never had any problems after a fill up . Is it just the gas gauge acting up or all the gauges ?
 


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#7
My parking space is at a slight incline. Nothing drastic.

2017 w/Recaros - bone stock
I used to see that when I parked on a decline (with the nose of the car pointing downwards). I park on flat grounds these days and I don’t see it happening anymore. Does that in my MDX as well.


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FiSTerMr

FiSTerMr

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Thread Starter #8
Do you have a gas cap or using the capless? I'm wondering if it might be sucking air in and causing it .I have a locking gas cap on mine and have never had any problems after a fill up . Is it just the gas gauge acting up or all the gauges ?
I have a locking as well. The other gauges are working.

2017 w/Recaros - bone stock
 


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FiSTerMr

FiSTerMr

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Thread Starter #9
I used to see that when I parked on a decline (with the nose of the car pointing downwards). I park on flat grounds these days and I don’t see it happening anymore. Does that in my MDX as well.


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That would normalize think once you're on level ground. In my case i would start to see the miles to empty actually increase as im driving. Then after a point of continuous driving it starts to go down. I can't say if it becomes accurate at that point, but it doesn't inspire confidence.

Im curious if the focus guys had that issue pertaining to the evap recall... Google search not coming up with much.

2017 w/Recaros - bone stock
 


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FiSTerMr

FiSTerMr

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Thread Starter #11
My gas gauge will show full after refueling for a day or so even after driving 50+ miles, then drop to 3/4 full al of a sudden.


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Do you have the rough idle gassing up issue?

2017 w/Recaros - bone stock
 


maestromaestro

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#12
In my uneducated guess, these two (rough idle and the gauge) may not be related - that’s one is not causing another. The gauge is essentially a display of the electrical signal from the sender, which had been processed by the ECU (or whatever CU deals with it). There’s some “learning” to that, apparently - for instance, if I flash a new tune (or the car battery gets almost completely depleted), the remaining range number is completely out of whack - it thinks I can get 450 miles on a full tank.

So, there may be 2 things going on simultaneously.
 


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#13
I do experience the rough idle after refueling, at the beginning I thought that it was because I was over filling it, but it really does it all the time for the first and second start up, no issues with fuel gauge yet.
 


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FiSTerMr

FiSTerMr

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Thread Starter #14
In my uneducated guess, these two (rough idle and the gauge) may not be related - that’s one is not causing another. The gauge is essentially a display of the electrical signal from the sender, which had been processed by the ECU (or whatever CU deals with it). There’s some “learning” to that, apparently - for instance, if I flash a new tune (or the car battery gets almost completely depleted), the remaining range number is completely out of whack - it thinks I can get 450 miles on a full tank.

So, there may be 2 things going on simultaneously.
I connected the two, because they are both gas related and both happen at the time of a full tank. Also, when I did a bunch of searching a while back, somebody mentioned that as an aside. That the vapors that are causing the car to stumble, could also affect the reading. That led to this thread... Figured if that's the case, more people would experience similar symptoms.
This is the only issues that I've ever had with this car, knock on wood. As long as there's no permanent damage from this issue, I could live with it... I guess. Seems less painful than wasting countless hours at the dealer, only to be told they couldn't replicate the issue.



2017 w/Recaros - bone stock
 


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#15
I connected the two, because they are both gas related and both happen at the time of a full tank. Also, when I did a bunch of searching a while back, somebody mentioned that as an aside. That the vapors that are causing the car to stumble, could also affect the reading. That led to this thread... Figured if that's the case, more people would experience similar symptoms.
This is the only issues that I've ever had with this car, knock on wood. As long as there's no permanent damage from this issue, I could live with it... I guess. Seems less painful than wasting countless hours at the dealer, only to be told they couldn't replicate the issue.



2017 w/Recaros - bone stock
Bumping this because I'm having a similar issue. Mine doesn't usually occur immediately after a fill-up (other than the occasional long start), but at around 3/4 of a tank, it starts to stumble and have a rough idle that occasionally causes a full stall when coming to a stop. When this starts happening, my gas gauge is almost always off. This morning, in fact, I caught it before the stall, but the gas gauge topped out again, even though my miles to empty did not change. I'm getting a purge valve code, so I have the EVAP hose kit on it's way from Woosh right now, so I hope it fixes the issue.
 


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FiSTerMr

FiSTerMr

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Thread Starter #16
Bumping this because I'm having a similar issue. Mine doesn't usually occur immediately after a fill-up (other than the occasional long start), but at around 3/4 of a tank, it starts to stumble and have a rough idle that occasionally causes a full stall when coming to a stop. When this starts happening, my gas gauge is almost always off. This morning, in fact, I caught it before the stall, but the gas gauge topped out again, even though my miles to empty did not change. I'm getting a purge valve code, so I have the EVAP hose kit on it's way from Woosh right now, so I hope it fixes the issue.
Do you have mods?
 


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FiSTerMr

FiSTerMr

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Thread Starter #18
None. It's a bone stock 17, just rolled over 30k miles.
Interesting. Same here, but at 20k.

Getting the stall issue outside of immediately after the fill up is not a common issue. If you are still under warranty, I recommend bringing it into Ford. Let them figure it out.

I have not noticed the inaccurate gauge issue repeat itself again. Not sure if it was a fluke thing or not.
I do leave the fuel nozzle inserted for 3+ minutes when filling up. That seems to eliminate the fill up stall issue. Still happened maybe once or twice, but that was out of 50 fill ups, plus when it did happen, it was much more mild.

As long as I dont get a CEL, I will leave well enough alone.
 


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#19
Not under warranty, unfortunately. My theory is that the purge valve is sticking, forcing dirty air through and causing it to stumble and stall. I'm hoping this replacement kit will fix the issue.
 


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FiSTerMr

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Thread Starter #20
Not under warranty, unfortunately. My theory is that the purge valve is sticking, forcing dirty air through and causing it to stumble and stall. I'm hoping this replacement kit will fix the issue.
I hope so too (y)
Please report back your findings. Thanks!
 


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