Wow, that doesn't sound too good.
Could be worn rings, resulting in pumping up the pressure in the crank case.
Ralph
Probably onto something there, the engine hasn't ran as it should for months now; poor mpg, not going as "fast" as it did previously.
Replaced the spark plugs yesterday but they weren't oily (very black sooty though)
Just did a 14 mile drive and it's filled 40% of the catchment tank 
