Thanks Andy
Sort of at the same point, trying to decipher cause and symptoms!
The ignition timing is 5 degrees retarded which I know on these at idle would normally be approximately 12-20' BTDC but is this a cause or symptom?
Will be double checking physical timing including removal of pulleys for key inspection and will post findings.
I agree that a throttle body should probably have logged a code which it has not, and actually KOEO the throttle butterfly moves slowly through full range of motion as the pedal is slowly depressed so working as it should, its being commanded wide open due to the manifold pressure I believe.

Will try the compression and ignition comparison but think it may not be accurate enough in this case? WPS will be on order Monday!

Regards

Luke Browne