gas station pumps dont shut off, tank over flows

[90K5]

So ive got a SES code PO442, means a small leak in the evap emissions system...cant be the gas cap, because when i fill up, the pump doesnt shut off when the tank is full, it overflows from the fuel filler hose or tank, something under the truck, because the paint doesnt get gas on it. Would a leak in that system cause the pump to malfunction? I tightened the hose clamps for the filler hose and reset the light, but it came back on. I replaced the pump not long ago, and had to drill a hole for the sensor (1 wire vs. 2 wire pump) but i really dont think thats the source of the problem. Truck is an 01 silverado with the 4.3...any ideas?

 

[sled_dog]

you drilled a hole in a portion of your gas tank and don't think thats the problem?

That WOULD cause a p0442, and would allow gasoline to leak out. Please tell me you use a gas safe sealant around the hole?

Evap leak monitor is one of the last items to trip in a GM drive cycle(actually think it IS last), so it will take a while to come back, but it will. Unless you have a scan tool to force it to run a Evap Leak Monitor.

I'm confused by your drilling situation. You got the wrong pump so you had to modify the tank? Or just the wiring? I know sometimes you have to cut and solder wires to replace a pump, but anything else doesn't make sense to me, unless its some universal aftermarket pump.

 

[90K5]

in the top part of my old pump/sending unit, the part that mounts to the tank, there was a hole for the sensor...the new one was supposed to be a direct replecement, but did't have the hole, just a knockout kind of thing, so i drilled one there. Sensor fit really tight, had to lube it up a little to get it to go in, and with the weather pack connectors, i really doubt its the problem.

 

[k204dr]

I would start with figuring out where the gas is coming out. that leak will cause the evap code.

 

[sled_dog]

I would start with figuring out where the gas is coming out. that leak will cause the evap code.

X2, find the leak and you found your evap leak. Sure you tightened everything when you reinstalled the tank? I'd look to the vent hose(the hose that runs up with the filler neck).

I am clear on what you had to do now. I thought you drilled a hole and just ran a wire through it, I see you meant the tank pressure sensor now.