After calling the AA as Bessie was leaking diesel on Friday the patrolman stripped down the fuel pump and replaced a seal. Fixed the fuel leak and we went on our way. An hour up the road the engine management light came on but Bessie drove normally so carried on to destination. Next morning driving to hotel the light was still on but now white smoke was being emitted when driving even after the engine was warm. Called AA again and they came out but couldn't connect to the diagnostics - our motor wasn't coming up on his Bosch system (apparently we have a Ducato 2.3 40 130 - but not sure how he could tell this). After his attempts to connect the light went out and engine ran fine (no smoke). On the way home down the M40 next day the light came on again and every now and then it lost power but I could accelerate through it. I think there may be an EGR valve issue as we had similar symptoms on another 2007 Ducato previously. I would like to confirm the issue as I first thought it may the water in fuel filter sensor as that was the part that was stripped down. Or could the EGR valve be affected by the Fuel Filter problem. Any ideas how I can get it diagnosed if the AA cant read the diagnostics?