Unfortunately I've not dug into those systems. There is the system that shuts off the outside vent save a known size orifice to measure the current on the air pump that pressurizes the tank to measure for leaks.

Then there is a master valve that shuts off the vent to the charcoal canister. If that valve is stuck shut you'll have the same problem. I don't know where the parts are but some might be in the left rear wheel well.

Open your gas cap after a long drive if you hear a crazy vacuum suck the problem is for sure the vent not opening


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2011 E70 • N55 (me)
2012 E70 • N63 (wife)