Gas nozzle shuts off, check engine light
Gas tank hard to fill, gas nozzle shuts off
Diagnose and fix gas nozzle shuts off, check engine light GM
If you have a check engine light on and a gas tank hard to fill where the gas nozzle shuts off, this post is for you. GM has issued a service bulletin 09-06-04-028D to address these issues on the vehicles listed below. In addition to the symptoms listed above, you may also have any of these trouble codes:
2007-2010 Cadillac Escalade Models
2007-2010 Chevrolet Avalanche, Suburban 1500, Tahoe
2007-2010 GMC Yukon Models, Yukon XL 1500 Models
Cause of gas nozzle shuts off, gas tank hard to fill
The EVAP system includes a canister vent solenoid to allow fresh air into the charcoal canister during a purge cycle. The Vent solenoid tubing is attached at the top of a conduit secured the fuel fill pipe. I’m not sure how the engineers missed this, but they’ve belatedly realized that dirt and dust can get sucked into this vent tube, resulting in restricted airflow during a purge event. In addition, these geniuses of engineering never thought about the possibility of water entering this vent tube. The water corrodes the vent solenoid valve, causing a restriction.
The water can also enter the cyclonic filter that was designed to protect the charcoal canister. If the water volume exceeds the holding capacity of the cyclonic filter, water can enter the charcoal canister, further reducing the canister’s ability to adsorb fuel vapors during fuel, which results in repeated gas nozzle shutoff even though the tank isn’t filled.
Fix for gas nozzle shuts off, gas tank hard to fill
GM has redesigned the canister vent solenoid with part #20995472. The new vent solenoid is a sealed unit that is vented through a pre-filter that mounts above the fuel filler housing.
Replace the canister vent solenoid
Remove the old canister vent solenoid:
• Open the fuel filler door (leave the gas cap in place) and remove the two TORX screws and screw that hold the fuel filler pipe to the body.
• Remove the spare tire
• Disconnect the wiring harness at the canister vent solenoid
• Clean all the EVAP line tubing and connections before removing the old canister vent solenoid components to prevent contamination.
• Disconnect the quick connect fitting from the EVAP canister. Then remove the canister vent solenoid bracket (save the bolts).
• Remove the zip ties and corrugated conduit from the canister vent solenoid and the fuel tank filler pipe. Then remove the entire canister vent solenoid assembly from the vehicle.
• Lower the fuel tank filler pipe housing enough to drill a hole in the housing
• Drill a .27” hole in the fuel tank filler pipe housing approximately .59” back from the base of the flange and .59” rearward of the forward housing attachment clip as shown. Remove any burrs.
• Place the revised canister vent solenoid into position in the vehicle and place the canister pipe above the cross bar brace, just forward of the CVS valve.
• Position the CVS valve bracket and install the bolt into the spare tire cross-car support. Tighten the bolt to 106/in/lb
• Connect the canister vent solenoid jumper harness, #19257603 between the CVS valve and the vehicle chassis wiring harness electrical connector. Secure the clip on the jumper harness electrical connector to the spare tire cross bar.
Note: The EVAP canister pipe MUST BE ROUTED ABOVE the cross-car brace, just forward of the CVS valve and BELOW the EVAP canister, as shown, rather than above the EVAP canister, as the original pipe was routed.
• Connect the CVS valve assembly canister pipe quick connect fitting to the EVAP canister.
• Position the CVS valve vent hose along the fuel fill pipe as shown.
• Position the CVS valve pre-filter on the fuel tank filler pipe housing as shown. Align the
hole in the CVS valve pre-filter with the hole that you drilled into the fuel tank filler pipe
housing. Install the pushpin, #10121502, from within the fuel tank filler pipe housing
securely into the CVS valve pre-filter.
• Secure the tie-strap to the vent hose to the fuel tank
• Install the other tie strap around the CVS valve vent hose on the fuel filler housing side of the strap.
• Reinstall the fuel tank filler pipe housing back into its original position, making sure the pre-filter screen openings are pointing down
• Install the spare tire and wheel assembly.
©, 2018 Rick MuscoplatPosted on by Rick Muscoplat