Foam in gas tank cause gas nozzle auto shut off before fill

My 2001 Chevy Prizm recently has this problem: when filling the tank (with #87 gas), the gas pump nozzle will automatically jump (shut off) about every 0.4 gallon or so, before the tank is filled. This keeps happening until the tank is actually full. I tried many different gas stations, I tried turning the nozzle upside down or any other angle, not helping. I noticed that foam comes up as gas goes into tank and that may trigger the nozzle’s auto shut off mechanism… Anyone has similar issue before? Any idea why this is happening (never have any problem for ~5 years of having this car) and how to fix it? Thank you very much!

Does the nozzle have too much extension into the filler neck? I’ve noted that nozzles are penetrating further into the filler neck. Have you tried pulling it out a tad? That said, the flow rate generally dictates the shut off level. Too high a flow rate …too much agitation attaining too much height above the liquid level.

Can you manually fill it without interruption? If so, it’s the minimum setting on the pump is your problem.

Since you haven’t gotten a code for the EVAP:PURGE, you probably don’t have any damage to the system.

Did someone make a habit of topping off the tank after the first time it clicked off? If so they may have damaged the vapor recovery system. Likely your owner’s manual makes note of this and there may be a sticker on your car warning you about this.

The problem might be with the Onboard Refueling Vapor Recovery system.

This system captures the fuel vapors in the carbon canister before the gas tank is allowed to vent. If there’s a restriction in this system the gas tank can’t vent properly so the pump nozzle kicks off.

Have someone inspect this system to make sure there are no restrictions.


Use the search feature of this board to view hundreds of posts on this subject…Try the words “gas fill” and see what that brings up…Sometimes you can dislodge a stuck check-valve by running a flexible rod down the filler neck…(Bicycle flag whips work great)…

I did not pay much attention to the nozzle, but they should be quite standard, I guess… I tried many gas station and have the same problem. I also tried sticking the nozzle further in or our, no difference.

I also tried pulling the nozzle as much out as possible so that the main inlet of the gas tank is open to the air (that’s how I see the foam), but as soon as the foam comes up, the nozzle shut off.

I have not tried mannually fill yet, I will give it a try and follow up here. Thanks!

restriction means some light is on or something like that? No, there is no light indicates there is a problem. It could be that the filter or the carbon canister is jam… any idea how to get to them? I’d like to clean them first and see if that makes any difference. Thanks!