"Christian McArdle" wrote in message
. net...
The pump is working ok (I only replaced this less than 2 years ago)
The motorised valve must be ok (Again I only replaced this less than 2
years ago).

Could you explain these statements. Why must the pump and motorised valve
be
OK?

Quite. Many years ago I thought I had identified an intermittent ignition
fault in the capacitor in my car distributor. Bought a new capacitor, tried
it, fault still there. Bugger. about a day later, having removed bits of
wiring loom, dashboards etc., I tried another capacitor out of someone
else's car. Problem went. Replacement I had bought was faulty. Grrr. I was
unable to take it back to the shop as I had reduced it to a two-dimensional
object with a 2lb lump hammer.

Bob Mannix