I had my M3W parked in my garage with a full tank 100% of 98 octane. No problem, except for a slow motor start. I am always careful to not over fill the tanks. I moved the M3W out onto the street to give access to the garage. My street is level & the day mild & sunny. About 40 minutes later a passing neighbour told me that fuel was pouring out of the rear of the the three wheeler. To gain access I removed the luggage space floor & observed fuel pouring from a vent pipe attached to the pollution control vapour collecting canister. I removed the fuel filler caps & the flow stopped. At the advice of the service agent, I had the M3W towed to their workshop.
They could find nothing wrong with the vehicle.
Apparently with a full tank, liquid fuel can build up in the vapour collecting capsule until it is full when fuel can then syphon out of the fuel tanks.
Advice was to only fill the tanks before I am going on a run.
The hard start problem was solved as their is a vapour vent from the engine to the canister. with a full canister fuel could also flow to the engine causing a rich mixture.
Has anyone had a similar problem? Somewhat alarming.
