Problems pumping gas pump clicks off after .3 gal even tho not full. I replaced the vent valve solenoid but still having same problem

Kaylie, try letting off on the gas pump trigger a little and pull nozzle out of fill port approx. 1/2", this will normally slow the flow rate of pump down and let air behind gas and stop shutting off. Some pumps are just set to pump too fast/ too much volume. If this does not work for you, have a Tech. check and see if there is some other restriction,plugged vent or problem with the vapor canister. Check the attached links,instruction and guides, Good luck
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Slow Fuel Fill Problem Diagnosis Hyundai Forum Hyundai Enthusiast Forums
Gas Pump Shutting Off
Problems pumping gas
https://www.reddit.com/r/MechanicAdvice/comments/2zhid3/hardtofill_gas_tank_2001_hyundai_elantra

Maybe tank is full? Could be something was shoved in the tube that runs from the gas cap to the tank.

Bad fuel evap system vent valve
or insects blocking solenoid vent

how long has the check engine light been on?

The vent solenoid is likely stuck closed. If you look under the vehicle you will find the charcoal canister back by the gas tank. There will be a large rubber/plastic hose coming out of the canister. On the other end will be the vent solenoid. Should be up under the spare tire area.

Disconnect the hose from the vent solenoid and then try to fill the gas tank. If there are no problems filling with the hose disconnected replace the vent solenoid.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

P1494 (M)Leak Detection Pump Sw or Mechanical Fault. Incorrect input state detected for the Leak Detection Pump (LDP) pressure switch.

The Evaporative LDP switch may be bad or the pump itself has a problem. Check the pump, the wire connections, and the hoses attached to it.





LEAK DETECTION PUMP (LDP)
OPERATION
The Leak Detection Pump (LDP) is used only with
certain emission packages.
The LDP is a device used to detect a leak in the
evaporative system.
The pump contains a 3 port solenoid, a pump that
contains a switch, a spring loaded canister vent valve
seal, 2 check valves and a spring/diaphragm.
Immediately after a cold start, engine temperature
between 40°F and 86°F, the 3 port solenoid is briefly
energized. This initializes the pump by drawing air
into the pump cavity and also closes the vent seal.
During non-test test conditions, the vent seal is held
open by the pump diaphragm assembly which pushes
it open at the full travel position. The vent seal will
remain closed while the pump is cycling. This is due
to the operation of the 3 port solenoid which prevents
the diaphragm assembly from reaching full travel.
After the brief initialization period, the solenoid is
de-energized, allowing atmospheric pressure to enter
the pump cavity. This permits the spring to drive the
diaphragm which forces air out of the pump cavity
and into the vent system. When the solenoid is energized
and de-energized, the cycle is repeated creating
flow in typical diaphragm pump fashion.

your evap vent filter is plugged. you can find it in front of the gas tank underneath. blow it out and it will be fine.

YEP HAVE IT SCAN AT AUTO ZONE OR ADVANCE AUTO THEY WILL DO IT FREE.SOUND LIKE YOU HAVE EVAPORATIVE EMISSION PROBLEMS DUE TO UNCONTROLLABLE GAS VAPORS BUILDING UP PRESSURE IN GAS TANK NOT ALLOWING YOU TO PUMP GAS.SOUND LIKE THE PURGE SOLENOID VENT TO CHARCOAL CANISTER NOT VENTING OR WORKING. IF YOUR CODE TURN OUT TO BE PURGE SOLENOID REPLACE IT.CHECK FUSE GOING TO SOLENOID FIRST BEFORE BUYING ANOTHER ONE.

have your evaporative purge valve solenoid check. because its controls the gas vapors going to canister purge or vent valve.take it to dealers have the evap system scan because its not venting or controling gas vapor.it suppose vent gas vapor to intake to be burn.if it dont work it causes excess gas vapor pressure built up in tank. make it hard to pump gas into it.

These fuel tanks are designed weird, they have a hump in the middle for the driveshaft. Most of the time I have found if the pump clicks off early it is the fuel vent valve, which is located on the rh side, but a fuel cut valve could do the same thing. If the pump clicks off early (sometimes after 1 gal), make sure the canister filter isn't clogged and replaced the vent valve.

i just went through that problem

Evap canister / close solenoid and air filter $211- 230.00 in parts

$675- $71.00 at dealships for this small 30 minute task

If no check engine light Evap canister and air filter - fixxes problem 100 %
note:you may be able to get by just replacing air filter- works
rarely

if have check engine- close solenoid and purge solenoid may need replace- you local autozone- like autozone will pull check codes for free

the how to:

Jack car up in rear - behind right rear tire - canister -canister close solenoid & air filter are located in a plastic box with metal strap and one bolt.

Unscrew bolt everything drops down the EVAP CANISTER is held to plastic box by wirer tie . Remove wire tie and solenoid connection.
There is a small metal wire clip the holds the solenoid electrical connection together with a flat screw driver pry up the wire clip , off is okay too , ....it will go back on.

Once you have done all that you have full access there are i believe from memory 3 rubber hoses with clips ......Mark hose connects very important mark the hoses way the going on evap canister with color tape .

Next, remove whole assembly- the solenoid and air filter will come with the evap canister.

Now that have the whole assembly move to your work bench
look to see how the soleniod hook up to the canister and the air filter - now, disconnect the hose to black solenoid and remove the air filter which hook to solenoid and solenoid at same to ......

Next seperate the the solenoid and air filter- you should be air to put your mouth on solenoid and blew air in one hole and out the other- this solenoid is noramlly open- if air dosen't go threw is stuck closed and must be replaced.

same with air filter- this air filter are know for get plugged and should be replaced every 30,000 miles.

Also note: over fill you gas tank , at fill up - can cause the Evap to get liquid gas inside which cause the chorcoal in the filter to swell up and plyug the system up.------ you should when fill up stop pump gas after the auto pump click off on normal work tank and not try to top off you tank.

note: check with your deal for exact wieghts
weigh the evap canister - six pound - replace it- new one is about 4-4.5 pounds - it is just best to replace .The evap holds gas fumes then send to engine so that dosn't vent to

All parts are dealships only -

This is easy fix and normal, for gas fill problems

canister Evap 161.00
canister close solenoid 43.00 may or may not be used
air filter 7.00

not used in this fix- check engine fix use these parts
sensor price ?
purge valve 39.00
canister close solenoid 43.00