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Wow, that's really odd. Where did they install the auxiliary pump?
As long as your OEM pump is in place and working, you can eliminate the extra one. The only reason I can think of for the extra pump is that they had problems with the regular one. Maybe had overheating problems and thought a second pump would help with cooling.
Ken Kanne, Silverhill, AL, Bimmerfest Site Moderator
Amateur Extra ham radio operator KO4AXN, see you on 40 meters!
1993 325is M3 clone"Ashlyn"; 1993 325is "Elvira"; 1985 635CSi "Katja"; 1984 633CSi "Sylvia"; 1987 325is "Odette";1995 318is"Bebe "; 1985 325e "Hazel Ann"