Evap solenoid - can it cause hard fill ups? 02 TB LS

[Berns]

A few weeks ago I had a hard time starting my truck after filling up. This past weekend I was filling up but it kept shutting off and gave me a hard time pumping gas in. Can the evap solenoid in the rear of the TB cause this issue? 02 TB LS

 

[The_Roadie]

I don't see how. A kinked hose (happens a lot) from the fill opening to the tank can do that, as well as a hair-trigger backpressure detector on the pump. Try a different pump next time, and inspect the hose.

 

[AtlWrk]

Certainly makes sense. That valve is normally open to the atmosphere to allow fuel to be pumped into and pulled out of the tank. There have been reports/pictures of it filling with crud and clogging or simply getting stuck closed. Not a particularly difficult or expensive part to replace. Just make sure you get the "vent" solenoid, not the purge solenoid--some auto part store counter jockies don't know the difference. You could even just pull the evap hose connected to it to see if your hard starting/fill up issue goes away to confirm.

 

[IllogicTC]

I would say it's more likely to be a kinked hose (slowing the rate at which fuel goes where it should be) or the pump itself. The pump "knows" when to shut off by having a small hole near or on the nozzle tip which has suction applied using a venturi. When the (entirely mechanical) setup in the handle detects an increase in the amount of suction required (by creating a vacuum), it shuts off. A dirty/clogged nozzle "detection hole," or a kinked fill hose (where gas is constantly at the fill nozzle tip) could trip the system.

The vent solenoid only opens during canister purging (except during EVAP testing, where the vent stays closed and the purge opens to test for vacuum), so EVAP shouldn't have anything to do with this.

 

[Hypnotoad]

Mine does this every time I fill the tank. I have to lift up on the nozzle, then it fills just fine.

 

[IllogicTC]

Mine does this every time I fill the tank. I have to lift up on the nozzle, then it fills just fine.

Yeah, mine too. I literally just lift it maybe 1" at the most (it'll sit either completely buried in the fill neck, or at this second position just slightly from flush) and it seems to work better. Have to get under mine and see if the hose is kinked.

 

[AtlWrk]

The vent solenoid only opens during canister purging (except during EVAP testing, where the vent stays closed and the purge opens to test for vacuum), so EVAP shouldn't have anything to do with this.

"The EVAP canister vent solenoid valve controls fresh airflow into the EVAP canister. The valve is normally open. The control module will command the solenoid closed during some EVAP tests, allowing the system to be tested for leaks." -AlldataDIY

 

[Hypnotoad]

I crawled under mine, and I didn't see any kinks or anything out of the ordinary. I guess I'm just lucky, I just love standing there holding the gas nozzle up in -40 degree weather.

 

[IllogicTC]

"The EVAP canister vent solenoid valve controls fresh airflow into the EVAP canister. The valve is normally open. The control module will command the solenoid closed during some EVAP tests, allowing the system to be tested for leaks." -AlldataDIY

My bad. It was explained differently to me.

Another issue I'm finding online when searching "gas pump keeps shutting off" is that people want to make the dollar amount even so they keep hitting the handle after it's initially shut off, flooding the charcoal canister with liquid gas which ruins it.

 

[C-ya]

Another issue I'm finding online when searching "gas pump keeps shutting off" is that people want to make the dollar amount even so they keep hitting the handle after it's initially shut off, flooding the charcoal canister with liquid gas which ruins it.

Any further explanation or a pic to look at? Is the charcoal canister between the tank and the fill port? What am I missing?

 

[IllogicTC]

Any further explanation or a pic to look at? Is the charcoal canister between the tank and the fill port? What am I missing?

No, the canister is part of a system to get rid of EVAPORATED fuel. Gas fumes. There's a line leading out of the fuel tank to the canister, and another line from the canister toward the engine. I can't recall the position, I believe it's right above the gas tank so it'd likely involve dropping the tank to access.

 

[sunliner]

I had the same problem with fill ups. I replaced the vent solenoid (on the engine block) and the problem with fill ups went away but I still had a 0455 code (large leak in the EVAP system). replaced the purge solenoid (by the gas tank) and the code finally went away.