Thanks for the response, the engine has just gone to 15471 so not many miles at all. I have no idea about the mechanisms around that area, I just kept cleaning them hoping for the best. Now that you mention it, the air filter does have an oil seal around the edge? Is that what you mean? I might replace the air filter now. Already replaced both lambda sensors and the maf! Not sure how much more this is going to cost me...Just thinking, if cleaning the MAF helps as it seems to, is there something that's causing the MAF to foul? crappy air filter or I was thinking is the crank case breather bringing up some oil vapour (nope, that connects to the manifold on CG13, is it the same on CGAs? Yours is a relatively new engine correct? so shouldn't have much blowby anyway).
Reportedly oiled air filters can play havoc with hotwire MAF sensors you haven't got one do you?