The truck is a 1999 Chevy Silverado the code is a p0446 and an evaporative emission system vent control circuit. Any help on how to fix would be great. Thank you Ryan.
The truck is a 1999 Chevy Silverado the code is a p0446 and an evaporative emission system vent control circuit. Any help on how to fix would be great. Thank you Ryan.
I'm sure you've checked this, but if not...is your gas cap on tight and in good condition? Those emission codes are very often caused by either a loose or cracked/poor sealing gas cap...
2011 Skeeter ZX225
225 Yamaha HPDI Series 2
Minn Kota Ultrex 112 52"
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Actually DTC P0446 is a Evaporative Emission (EVAP) Vent System Performance code not vent control.
What engine?
Charcoal canister need replaced? They get full of dust and no amount of cleaning can fix it
The evap is easy take it to a parts store and ask them to test your gas cap. They have a device to put on it that pulls a vacuum to see if the cap still seals. They will also put that over the fill neck and pull a vacuum on the fuel system. If the caps bad replace it. If the system won't hold a vacuum then the evap line running back to the tank is bad. Coming out of the top of the fuel sending unit is two lines one solid metal (fuel) goes to fuel filter then forward. The other has rubber then metal that's the evap line the rubber goes bad with age.
Vent solenoid is probably bad. My 06 has had the same code for years. The 06 had a bulletin for vent solenoid replacement and filter relocation.
just checked, you have same bulletin 02-06-04-037J. I would test or replace the vent valve. Rockauto has them
"There is nothing more free, than one who has nothing to lose"
^^^^ This ^^^^. Vent valve solenoid sticking associated with that code.Originally Posted by mwill29
And that right there is bad advice.^^^^^^^^^
"There is nothing more free, than one who has nothing to lose"
In what way? I paid a shop to test mine but he told me autozone can do the same thing.
You would have to plug the vent in order to pull a vacuum on the tank. They can test the cap.
"There is nothing more free, than one who has nothing to lose"
My money is on the canister as well. When I bought my Avalanche the dealer replaced the solenoid and everything but the canister. Nothing fixed the problem. They finally sent it to their Chevy store 10 miles down the road, replaced the canisters and no problems since. At least I got a bunch of new parts out of the deal.
All I know is what the man told me. After vacuum test of the cap and fuel system a evap line was bad. He told me to take it home leave it running and spray the evap line with soapy water. He was right bubbles everywhere when you find the leak.
There probably right on the canister but check your filler neck mine rusted out and created a leak in the system
A smoke test is really the only way to reliably test for an evap leak. There is a canister vent solenoid attached to the canister that can get stuck open or closed and throw your evap code, that usually is the first culprit to check and a simple fix
At the manifold there is a purge valve that can also get clogged if you have had any charcoal get out of the canister into the system. If you have overfilled your tank it can damage the canister itself allowing charcoal to foul the entire system, hopefully that
is not the case here.
You can usually get both the vent solenoid and purge valve at any good local parts store.
circuit code not a leak code. I just went and looked in my shop for a solenoid to take a pic and show you what happens but couldnt find one. As stated there is a bulletin for them. They get moisture and rust internally. The bullentin moves the filter/vent from the tank up on top of the transmission
2011 Ranger z521/2023 250ProXS
Where is it located on top of the transmission?
Very common for that evap line to rust out. Had to replace mine. While your at it change the evap canister, its cheap
The bulletin has you run a rubber hose to move it there. The solenoid is on the canister on the tank
2011 Ranger z521/2023 250ProXS
19152345 I believe it the number you would need. The bulletin is for the vent plugging but I have seen A lot rust internally
2011 Ranger z521/2023 250ProXS
XPRESS H 18 SS, YAMAHA 115
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