Largo VP37 pump question

[Tony]

Hi chaps,

My shiny new Largo came with a problem (which is why it cost about 1/3rd of the going price for a 40k mile version) - it will sometimes stall out when put into drive or neutral.  It idles quite low and the sudden load seems to be what causes the stall.

I've had a few days of trying to get the engine light to blink fault codes at me unsuccessfully - but finally I've found an appropriate adapter and software for the car - which I'm demoing in a video here should you wish to hear my dulcet tones   http://www.youtube.com/watch?v=ye25YKnwPw4

The ECU reports a fault with the "Fuel quantity adjuster/position sensor"

Now this bit is a horrible variable induction transformer sensor with no user serviceable parts - my question for the forum is this:

Can I remove the electronics module from the top of the pump and replace with another, from say, a Nissan Primera - which has the same engine - or is it a whole pump in/out job?

[Julian]

What do you have to loose by trying the sensor first?

[Tony]

The problem is that I don't know if it is detachable from the pump without damaging it.  I assume it must be possible.

Sensible first step is to probably take the top off and check for dirt/water and that the actuator moves freely to its extremes.

[julesandtash]

I'm sure HC-II will be along soon to confirm but I seem to remember him saying that if the electronics module is not put on exactly right with respect to the mechanical components of the pump, the engine can either fail to start or rev to destruction as soon as it does start.

Certainly I would not expect the electronics from another pump to fit it.

I do wonder whether a complete pump from another engine of the same displacement and power output would work though. It is the ECU that controls pump timing, fuelling etc after all

[Tony]

I'm sure HC-II will be along soon to confirm but I seem to remember him saying that if the electronics module is not put on exactly right with respect to the mechanical components of the pump, the engine can either fail to start or rev to destruction as soon as it does start.

Certainly I would not expect the electronics from another pump to fit it.

I do wonder whether a complete pump from another engine of the same displacement and power output would work though. It is the ECU that controls pump timing, fuelling etc after all

As you say it's the ECU that does the business regarding fuel quantity injection.  All these VP37s seem the same but I know the fuel temp sensor has different part numbers between them so what else?

As far as I am aware the only other sensor the VP37 uses is a hall sensor on the gear that would normally drive the governor shaft, so I don't see how position is important so long as the actuator shaft engages the ring on the high pressure pump OK.