Buzzing under back seat Type 44

[Huw Powell]

> Try removing the fuel pump relay and put a wire link in its place so
> that the fuel pump will run continually with the ignition on but
> engine not running. This should confirm if the noise is from the fuel
> pump.

That works, but you should use a wire link with a fuse in it for safety.

> If you dont want to use a wirelink just swop the FP relay with
> its extra ignition sensing pin for a standard relay that is doing
> nothing important in the fusebox.

That won't work, the trigger coil connection of the "standard" relay
will not be energised.  I think they did this on purpose, since th
substitution of a simple SPST relay would eliminate the tach signal from
the FPR - a ve important safety function.

--
Huw Powell

http://www.humanspeakers.com/audi/

http://www.humanthoughts.org/