Plugged H2 Evap Cannister

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Plugged H2 Evap Cannister:

Plugged Evap Canister....check engine light, DIAG Code P0446:

The charcoal evap canister (located on the passenger side frame rail) can get full of muck because the evap valve sucks it in. The evap system runs a vacuum test on the fuel tank integrity at random by putting a vacuum on it, never above a 3/4 tank of fuel, and never below a 1/4 tank of fuel. If you keep the tank full when wheeling, it wont be a problem. It was just bad luck that mine filled with muck......the system ran the test just at the time I was going thru muddy water. If you drive in dusty conditions, it will also eventually fill the canister with dust. Street queens will probably not have a problem with the evap system, ever. The only thing you can do about it is to keep the fuel tank full when wheeling.

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