Hi all. Many thanks for your interest and responses. The answers to your questions are as follows: Cam, Crank and 02 sensors are new and fitted on advice from another garage. The guy is a time served mechanic (no longer in the trade) and he double checked cam timing the day after he fitted timing chain. The vacuum at idle was 20"hg and the same at about 5000 revs in neutral gear. I think my gear only measures MAF in voltage terms ie: 1.3 volts at idle and low 3 volts at 5000 rpm in neutral. However will double check that when I go back and measure wot in 3rd gear. The emissions are 0% CO, 0ppm HC, 16.1% CO2, and 0.3% 02. and about the same at 5000 ppm. I have essentially ruled out cam timing at the mo due to good vac and emmission readings. Customer tells me tonight that 2nd hand MAF sensor made the vehicle drive worse than the original one, so there is a question mark there. Can't check part numbers on MAF because the original one strangely has last 3 digits rubbed off. Will let you know outcome on return visit. Many thanks Pete