Engine malfunction light on , scan showed fault P0235 Turbo Charger Boost Sensor malfunction, car was serviced this week and found this fault, but the engine feels to be running ok, I have done very little mileage in the last few years and very little motorway use and my mechanic says there is a carbon build up so give at a good motorway run these last few days and in low gear and pedal down I am sure turbo kicked in, just want to know if it is safe to carry on driving it with engine malfunction light on, with my late wife being disabled we have had motabilaty lease cars for the last 24 years and have forgot what under the bonnet looks like and can tell you it is a lot different than the it use to be LOL, so would be grateful for any help.