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On 7 Jan 2002, at 8:28, cheflayne@yahoo.com wrote: > On January 6 Jim Adney wrote:The hum you hear is most > > likely the fuel pump running. In doing this test it > > will only run in the ~1 second time between the 2 > > clicks.If you hear the 2 clicks with the pump running > > in between, then your system, including the wires to > > the starter, is connected properly. > I have 72 sqbk FI. I am experiencing some of same > symptoms. When I turn my key on, I here the first > click and then the hum, but I never hear the second > click. What is the second click? Thanks, Layne The first click is actually 2 relays closing at the same time. These are the main power relay under the back seat, and the fuel pump relay under the dash. Once this happens, the fuel pump will run. After ~1 second, if the engine is not started, The FI brain turns off the fuel pump relay, stopping the fuel pump. The second click is the sound of the pump relay opening. It is a common problem with 72s that a pair of wires to the starter gets reversed when the starter is replaced or serviced. This will "fool" the FI brain into thinking that the starter is running and thus it will not turn off the fuel pump relay. This causes a number of problems, including poor gas mileage, missing, fouled spark plugs, loss of power, and rich running. This can also happen to non-72 cars, but it is not quite so common. At any rate, if you don't hear the 2 clicks when you do this simple test, this is a problem with a very simple fix. This problem is specifically mentioned in the Bentley manual. - Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ------------------------------------------------------------------- Search old messages on the Web! Visit http://www.vwtype3.org/list/