Stall/stumble/stutter

[maestromaestro]

What I have is something that has been reported a number of times with variations, but I could not find a good answer to the cause and remedy.
My 2015 (stock evaporator harness) has started stalling - not after a fill, just at traffic lights. Now, with the coronavirus and staying at home, it doesn't get driven very much (actually, barely). It had some period stutter here and there before, but now it is pretty much there all the time - on short commutes, at a stop I have to keep goosing the throttle to stop it from stalling out.

I haven't had by AP hooked up to see if there are any codes showing up (should do it, I suppose). But, based on the swarm knowledge of the interwebs, ti would appear that it is related in some fashion to the evaporative system. (I have changed the filter a few months back, but it hasn't made any difference in the car's behavior).

Anybody out there who can steer me towards the answer? (Again, stock evap, new canister, NGK 1 step colder plugs with 5000 miles or so on them; and - the symptoms are worse now without any change to the above).

Much appreciated in advance!

 

[TyphoonFiST]

See if there are any stored codes first. Report back and one of us will help you with an answer.

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[maestromaestro]

See if there are any stored codes first. Report back and one of us will help you with an answer.

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Aye, Captain!

There are a few:

P0454
P2122
P2127
U0422

The second and third may be linked to when I replaced the battery a few months back. The oxygen sensor - not sure, but I did replace both of them last year. The first one is the evap one...

So - thoughts?

 

[TyphoonFiST]

Have you replaced the evap. Solenoid?

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[maestromaestro]

Nope, all as-bought in evap, save for the canister.

 

[TyphoonFiST]

Do you have access to a scantool to run a self test of the evap system to single it out?

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[maestromaestro]

Do you have access to a scantool to run a self test of the evap system to single it out?

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No, I do not. It's just me and the trusty AP.
Poking more on the web, it would appear that the 3 major culprits for this behavior are:

1) Vapor Canister (D2BZ9D653A)
2) Vent Control Solenoid (9U5Z9F945C)
3) Purge Valve (CX2456 - C1BZ9C915A)

As I said, I have already replaced the canister; the other two are about $50 combined, give or take. I don't mind replacing them, but would rather not go through the trouble if these are not what causes the symptoms.

Can it be anything else in the evap system or possibly be unrelated?

 

[maestromaestro]

I could look into getting a scan tool, but these are either way too expensive, or - at the cheaper end (like Bluedriver) may not be any better than the AP.

 

[maestromaestro]

So - anybody else have an idea as to what's going on?

 

[The_Ryan]

Sorry to revive this @maestromaestro , but did you ever find out what this code ended up being? Every thread I’ve seen has ended with no resolution. I just had this code pop up today, but no stumbling. Cleared it for now and refilled the fuel tank, hoping it was just a fluke or something

 

[maestromaestro]

Sorry to revive this @maestromaestro , but did you ever find out what this code ended up being? Every thread I’ve seen has ended with no resolution. I just had this code pop up today, but no stumbling. Cleared it for now and refilled the fuel tank, hoping it was just a fluke or something

No. The pandemic really impacted my driving - so, I am not behind the wheel more than an hour a week, all in short trips. It still does stall - not every time, but frequently hesitates, the revs drop but not quite stall. I'm reasonably sure it's one of the evap system components. I haven't had the AP connected for more than a year - time to check if there are codes. Passed state inspection - but here they don't check emissions. Or look underneath Or have a sense of smell. Straight pipe, baby! Yeehaw!

 

[The_Ryan]

hmm. I def don’t have any of those problems. Just the lone code. weird. fingers crossed it doesn’t return

 

[ray02945]

hmm. I def don’t have any of those problems. Just the lone code. weird. fingers crossed it doesn’t return

Ha running into the same issue myself.... People are posting here asking for help but i dont see the issue being resolved.
Unfortunate that all these threads, this one included, are so old.

P0456 issue here, purge valve was replaced as prev maint. however the smoke test came up clean, no stumbling whatsoever. Gonna have to just throw parts at it until its fixed i guess,

Canister solenoid then canister next.

 

[FiestaSTdude]

Do you have access to a scantool to run a self test of the evap system to single it out?

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Can you flesh out what you mean? My car has evap codes and I’m not sure how to make them go away so I can pass inspection. What does this self test tell you?

 

[TyphoonFiST]

Can you flesh out what you mean? My car has evap codes and I’m not sure how to make them go away so I can pass inspection. What does this self test tell you?

The evap system will quickly go through a Test every time the car is turned on. It will test the pressure and solenoids etc to see if it can operate correctly within OEM parameters. If it test and doesn't meet the criteria set by fomoco it will se the MIL/ Check engine light.

 

[TyphoonFiST]

Most scantools can and will do an Emission based test to check out the system to make sure it will operate correctly.