[Hi-Country]

That's a well written plan of attack. Those peculiar funky PITA retainer clips are not for those who have very little patience left. I got the first green U-shaped clip off w/o issue, but after wrestling with the white/tan one I broke 1/2 of it. Yes, I stopped at that point. All the while I'm laying on my back with cannister just inches from my nose...not the best posture for this 1st attempt.
To reiterate, I don't have a 'check engine' dash light showing at this time. What about having local Auto Zone personnel use their OBD reader. Good idea??? I'm thinking they offer this service. Will find out.

 

[davester3500]

Depending on what's gone wrong,you may or may not get a code. My truck did have a code for an evap leak, which I believe was due to a flexible line going to the engine being rubbed through, but that was unrelated to the fuel fill problem I had. I didn't think to check the canister, but I'm fairly certain that was the problem (that at least the port to the vent was plugged/blocked.

 

[Hi-Country]

If the ECM or is it the ECU is operating correctly and there is an algorithym not satisfied in this case the proper Evap system and we (owners) are having similiar but maybe a slight component differences why isn't that being flagged (throwing a code)?

 

[davester3500]

It doesn't have sensors for everything, so it can't necessarily throw a code for every condition that might go wrong.

 

[Hi-Country]

It doesn't have sensors for everything, so it can't necessarily throw a code for every condition that might go wrong.

Isn't that the ability of the bi-directional OBD, forcing each function to eliminate cause.

 

[davester3500]

Isn't that the ability of the bi-directional OBD, forcing each function to eliminate cause.

It works together. The bi-directional tool can order, for example, the evap vent solenoid open, but you have to blow through the tube (or otherwise check) to actually check that air can go through it. The bi-di tool can't tell if the solenoid actually opened/closed, or if the hose is plugged.

 

[Hi-Country]

FWIW, I'm the second owner of this '17 truck...it had 119K miles on the clock when I bought it Jan 2021. I don't think I've put 1K miles on it to date. Kind of letting the years catch up. Very high mileage vs. years although it was mostly highway miles. A contractor criss-crossing the US chasing the money. Carfax had a well documented paperwork trail established. 1st owner did his due diligence having it serviced at scheduled intervals at various dealerships along his journey.
So, again assuming it was feed with the recommended 93 octane its whole life...could fuel quality be a factor causing premature Evap system problems? Overfilling the tank is possible scenario.

 

[Stolisan]

Isn't that the ability of the bi-directional OBD, forcing each function to eliminate cause.

It does. The ecu tests the evap system every drive cycle. It tests for leaks by letting engine vacuum lower the pressure in the tank and closing the valves seeing if it can hold a vacuum. If it can't you'll get a code.

It also opens the valves and measures the vacuum in the tank. Too much or to little vacuum will give you a code.

Like I said before, you could be under the threshold of throwing a code but enough to be a problem filling gas. This was my exact problem and eventually years later, the CEL came on.

 

[Hi-Country]

It does. The ecu tests the evap system every drive cycle. It tests for leaks by letting engine vacuum lower the pressure in the tank and closing the valves seeing if it can hold a vacuum. If it can't you'll get a code.

It also opens the valves and measures the vacuum in the tank. Too much or to little vacuum will give you a code.

Like I said before, you could be under the threshold of throwing a code but enough to be a problem filling gas. This was my exact problem and eventually years later, the CEL came on.

And which component ended up being the source of the problem and did you effect repairs or did a dealer or local shop? Thanks

 

[Stolisan]

And which component ended up being the source of the problem and did you effect repairs or did a dealer or local shop? Thanks

See post #6

 

[Hi-Country]

See post #6

My apologies...you fellows have provided so much insight to a system I'm not familiar with that my head is spinning. If I could just get those funky retaining clips attach to the cannister to cooperate I'd be in good shape.
Did someone chime in earlier and noted that like most things there is a YouTube vid out there addressing that exact topic?
Thanks again to all.

 

[Hi-Country]

Been mulling this over...I have no check engine light, no codes, this most recent fueling issue wasn't there 2 yrs. ago. The truck has been parked in the dry for the past (2) yrs. with the exception of a 10 -15 weekly warm-up. Barely up to operating temp.
This prolonged idle period hasn't been the best thing for this truck. This might be a stretch but it could very well be that the canister (carbon pellets) have possibly partially solidified due to amount of moisture the system has absorbed simply by sitting. To me that seems like a reasonble assumption.
I was told to add a good fuel system cleaner and DRIVE it! Before I start throwing money and time at it. Its only a theory however remote it may sound.
Realistically speaking...very few things are self-healing and I'm not holding my breath here either...but drying things out at operating temperature can only be beneficial. 🤞

 

[davester3500]

fuel system cleaner will do nothing for the evap canister, or evap vent system.

So you started disconnecting the evap canister, busted off part one of the ports, and just stopped working on it?

 

[Hi-Country]

fuel system cleaner will do nothing for the evap canister, or evap vent system.

So you started disconnecting the evap canister, busted off part one of the ports, and just stopped working on it?

No ports are broken...accidentially split the thin (tan) secondary clip in two after removing the (green) horseshoe (primary) clip...on the fuel tank vent port. STOPPED WORK. I need to get a better understanding exactly how each of the (3) different style clips were intended to detach w/o breakage if thats possible.
Very easy straight forward part for part swap out after that. And more than likely I have a canister that has gone bad from sitting for prolonged periods.

 

[Hi-Country]

Update - Over the past few months I've been filling up w/o any burping, premature nozzle shut-off or anything else for that matter since I started filling up at another station in town.
It seems my isolated issues had something to do with the finicky pump/nozzle @ the local Murphy/Walmart station.
So, in the short term it doesn't appear like there is any blockage to raise concern as otherwise thought.