t4d engine manager and over run

hi, just got a td4 2001. picked it up at the weekend, and had no issues in the 400 odd miles except i noticed a small patch of fuel leaking on the ground. We tracked it back to the pump on the top of the tank, and more specifically around the seal. Apart fromm that all running very well. I took it to my local garage today who have always serviced and MOTd my cars since i could drive so i know they are good at what they do and are very fair and reliable. They re-fitted the seal and tightened the collar and I went on my way. When i got back to work, about 2 miles away, then engine management light came on, so i switched it off and it kept running for a few seconds. OK, i thought maybe a bit of an airlock or something had occured so I took it for a hard quick drive up the road and back, just to clear it out as such, and then went back to the office, got back and same issue with over run. Unfortunatly i had to go back to work, so I thought nothing of it until i left. Got half way home and the light came on again, engine was running all ok though, now roughness, nice and smooth, pulling well in all gears, not excessive smoking etc... Got home and it over ran again. Had a check under to make sure nothing had come adrift on the pump and all was ok, couldnt see any leaks or anything, but still over running, only for a few seconds, but enough not to be usual. Anyway, took it out again for a little drive, and pulled over, switched it off for a few mins, tried to start it again but it didnt. Tried a few more times, still nothing. Just reaching for the phone to cal the rac, and it eventaully started. All running well, nice and smooth etc... drove home. Got back and turned it off, and it over ran again, enough for me to take the key completely out and more or less get out the car. Any ideas? as re-fitting the seal shouldnt make that much difference should it????

Thanks in advance!

Turbo seal?

ok, but why that? all running fine before the resealing of the tank pump?

coincidence?

when yu have discounted all the probable answers, start thinking of the improbable .

yu say it runs on - that means it is still getting fuel after you have turned the engine off. Doozils normally have a fuel cut-off switch. this is either working or it isnt. if it isnt switching off, yu will still get fool. if it is turning off then the injun is getting "fuel" from somewhere else - the most likely cause is engine oil coming thro the Turbo seals

ok, but why would it run any differently after the garage has resealed the pump in the tank?
Its back to the garage in the morning anyway, so they can sort it out for me - i'll post the answer once they have dealt with it. I even joked with them today that i should have kept my reliable little diahatsu 4x4 - 3 years of ownership and only a waterpump replaced - 3 days with a land rover and the problems start. Never again.