P0451 and P0446 '07 Sub 5.3

[Siouxicide]

I've done a search, read the sticky, etc. I'm getting these codes:

P0451 - evaporative emissions control system pressure sensor range/perf
P0446 - evaporative vent control circuit

1. Have others seen this and is there a simple solution?(I've replaced gas cap already)
2. GMMerlin mentioned vent solenoid, but where is it located on a 2007 Suburban 1500 5.3L? And the canister? Anything else I should be checking? I assume these parts will not be clearly marked.

Thanks in advance.

[Siouxicide]

Originally Posted by Siouxicide

I've done a search, read the sticky, etc. I'm getting these codes:

P0451 - evaporative emissions control system pressure sensor range/perf
P0446 - evaporative vent control circuit

1. Have others seen this and is there a simple solution?(I've replaced gas cap already)
2. GMMerlin mentioned vent solenoid, but where is it located on a 2007 Suburban 1500 5.3L? And the canister? Anything else I should be checking? I assume these parts will not be clearly marked.

Thanks in advance.

After some other searching, I found that the vent tubing that's attached to the vent solenoid (and ultimately the charcoal filter and gas tank) can become plugged with mud/dirt. The vent end of the tube is held in place by wire ties along the fuel filler neck.
I found that mine was packed tight with mud. I cleaned out the mud and the light has been out ever since. I can only assume that was it.

[j cAT]

Originally Posted by Siouxicide

After some other searching, I found that the vent tubing that's attached to the vent solenoid (and ultimately the charcoal filter and gas tank) can become plugged with mud/dirt. The vent end of the tube is held in place by wire ties along the fuel filler neck.
I found that mine was packed tight with mud. I cleaned out the mud and the light has been out ever since. I can only assume that was it.

being a 2007 I thought GM moved this vent. my 2000 can have these issues when off road operation . the problem most times is overfilling the fuel tank causes liquid fuel to enter the canister. then the charcoal breaks up and clogs up the vent lines/solenoid.

my 2000 does not have this vent located on the fuel filler neck .I would see if you could place some material in the rear wheel well to reduce tire slop from getting up in that area..