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Fred See Diagram item # 12 Change-over valve, leaking or stuck half-way open. Fuel Change-over Valve P/N CBC4269 Can be found by removing trunk board to get to spare tire. (Diagram is for S3 so may be some differences in S2). Some have had luck cleaning insides with carb cleaner; if your tanks are full you are going to get a lot of gas spill, be prepared or as Doug would do, stick some pointed 1/2" wooden dowels into the hose as you pull it off valve nipple.
Last edited by David84XJ6; May 20, 2019 at 03:45 PM.
My 87 would draw from whichever tank I selected but always sent the return to the right tank, never the left. It seems the electrical connections for the return valves in the rear wheelwells were corroded. I fixed those connections and everything works properly now.
My 87 would draw from whichever tank I selected but always sent the return to the right tank, never the left. It seems the electrical connections for the return valves in the rear wheel-wells were corroded. I fixed those connections and everything works properly now.
Fred, I may have miss read your question, If one tank is filling from the other while driving, then as said above, it's the return valve (#2) not operating properly (electrical problem or the valve is gummed up)
