marc wrote: ↑21 Jul 2020, 14:40
As a matter of interest what is: -
a). the electrical connection on the pump just below the "unleaded" print on the rubber hose at the bottom of the picture?
b). the electrical connection in the centre of the injection pipes at the back of the pump, which is obscured by the throttle cable?
Can't help you with your idling issue but......
The injection pump was designed to operate with a very basic form of Electronic Control Unit (ECU) [E D I T] but the AAZ is not a tdi [/E D I T]
a) is the commencement of injection solenoid which adjusts the timing according to what the ECU is telling it.
b) is a sensor which sends a signal to the ECU when pressure rises in the pipe to the injector.
As you haven't got an ECU these bits won't do that, and the pump will behave pretty much like the older version which didn't have them. The timing setting might be slightly different, but I don't have any experience with that.
This picture is relevant.

Not my picture, so thanks to whoever posted it.