[V8] Motronic part numbers

[Peter Littlewood]

Hi Folks !
Sorry for the delay at responding to all of you emails... Thanks for all the advice. Finally dug the V8 out from the snow to have a good look at her. I've attempted to "blink out the codes" with a suitable LED and resistor. However instead of it flashing anything useful  at me, it simply comes on as soon as I connect it... get brighter when the ignition is switched on and then go dimmer again once the engine is running.
I'm getting a good 12v supply from plug 1 and the pin on Plug 4 is definatley connected to pin 22 on the ECU. But when I connect my mulitimeter between plug 4 and ground I'm getting 2.5Mohm. which is probably enough continuity to make the LED light up. I've disconnected the ECU harness and checked the wiring from the multiplug back down to plug 4 in the footwell and it seems to be fine. 
So, I think I've got an ECU earth fault which means I can't retrive the codes and can't sort out any of the other issues !!!
However I have changed the cylinder head temp sensor and it seems to be running better. No where near as much black smoke as before and I can actually stand by the car without my eyes bleeding !
Unfortunately I can't take her for a drive because she is not insured at the moment.
Any thoughts on the ECU issue, most welcomed !!
Cheers

Pete Littlewood