Right so I've changed -
MAF
Unplugged
Crank sensor / Needle lift sensor / Coolant sensor / TPS
Problem still remains, upon unplugging the crank sensor, needle lift, coolant and TPS check engine light comes on and stays on all the time which I guess is expected behaviour.
TPS unplugged the accelerator pedal does nothing, which again is expected.
Engine idle speed is slightly high (about 900 rpm), gets higher with things unplugged (about 1100 rpm).
Lift pump is ok - checked with the manual priming lever definate pressure from the bleed screw on top of fuel filter.
Only thing I can think of left is the injector pump timing? But the only thing confusing me is sometimes the engine goes real smooth for maybe 10-15 seconds then its back to being lumpy, if it was the pump timing surely it would be off all the time?