Defective charcoal canister affect UOA??

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Dec 4, 2004
Lexington, KY
I just replaced my charcoal vapor canister on my 95 BMW 525i with 111,000 miles. Would a defective canister affect UOA? My last two UOA from Blackstone showed fuel dilution issues. Crankcase ventilation was suspected.

Yesterday I replaced my plugs after 31,000 miles. All were worn normally with thin light tan deposits. I also use FP60 and mostly Chevron 93 octane.

Of course I could have one or more bad coils or fuel injection issues. Just trying to eliminate potential issues. TIA
Some evaporative emissions systems use a vapor (?) valve, to prevent liquid fuel from getting into the lines and the container. The system on my 93 Taurus used a purge solenoid with plastic that got brittle and cracked when it aged, letting unfiltered air in the intake, and long lengths of poor quality vacumm hose that rotted and cracked, letting yet more unfiltered air into the intake. Currently it's plugged while I look into possibly having to change all the line from the fuel tank at the back of the car, to the front of the car on the pasenger side, crossing to the driver side above the wheel well into the cannister, down to the bottom of the engine, back to the top and across the engine, and then into the intake. So far though I'm going on the assumption that Ford and the EPA didn't intend the system to last very long, so I can take my time fixing it.
My bmw does not use a pcv valve. However, there is "fuel tank breather valve", computer controlled between the canister to the throttle body area. I need to check if it is operating properly. However, no codes to indicate failure. Hoses "seem" fine.
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