Loss of tyre pressure

[redfox1]

have your tyre fitter remove the tyre, replace the valve, clean up any corrosion on the wheel and then refit the tyre using the bead seal black sealant (like liquid rubber), rebalance your wheel, your problems should be solved, shouldnt cost much at all maybe £10 piss easy job for a tyre fitter. even the likes of ATS or national tyres or bathwick might do it

Yep-deffo going back to the tech to see if he can fix-this time I'm going to ask where any possible corrosion is,and see if it can be addressed.Since yesterday the back tyre lost about 2 psi,front wasn't so bad,but both still losing pressure,so I've no alternative-Thanks for all the useful advice,folks :thumbup