Steve; It's not knackered. When we had a failed valve a few weeks ago, I got 150psi on all cyls (except for the 3 on the failed onehere ). One thing is the bores etc. I think the car's been used for tootling about for it's 74,000 miles. The bores have a brown tinge to them. We've given the car a number of 100 mile runs at dual carriageway kind of pace and the oil consumption has reduced. The trouble is, that it increases again due to the short (2x10 mile) trips that it gets daily.
Maybe Les's idea of getting it diagnostic-ed is the way. Trouble is, I don't usually let garages anywhere near my cars. They haven't generally impressed and if you've got enough time, I'll tell you tales that will curl your spanners up. I've got an oscilloscope that ought to tell me what it's outputting.
With the compressions up in the 150psi, I don't think the problem is blow by, more like lack of oil control.
Looking at the full set of numbers, I've an idea that the Lambda probe is giving the wrong output and allowing overfuelling slightly. There's not much O2 left to complete combustion. If I gave it a good hard run and got the Lambda probe hot, then it ought to get clean. I can't see how a Cat can turn CO into CO2 unless it's got some oxygen to do it with. There isn't a lot at 0.15% is there.?
The other way might be to drag the car into the road and set fire to it. It's come pretty close to that more than once.
I'll go and have another drinkie now and see if that helps me eeeerrrrrrrrrrrrrrrrrrr,