I have two problems that may be connected.

1. Everytime I fill up with gas, the first time I turn on the engine (still at the gas station), it fires with difficulty as if no fuel reaches the engine. The emptier the tank is before I fill it up the more evident is the problem.

2. After I burn 20 litres of gas, at about the 50ltr mark, the lambda lamp lights. This will continue for another 20 litres of fuel and it then switches off by itself !!!

Does anyone have any idea of what it could be ?

Could be your fuel filter. When did you change it last. If the filter is dirty and the tank is really empty, it might be hard for the fuel pump to do it's thing. Could also be the fuel pump. Mine failed 2-weeks after I bought the car (used). Before it failed, the engine would stutter before starting, like if you don't hold the ingnition key long enough. You might want to check if there are any fault codes in the computer relating to the fuel system.

I'd recommend filling up before the gas light goes on. It's hard on the fuel pump when the tank is really low.

After reading your post I remembered an instance where after a long drive I could not restart the car. The engine turned OK (i.e. battery etc were good), but it appeared that no fuel reached the engine. The next day it started fine and had not the same problem since.

I change the filter at every service, and if the problems are caused by the pump I would like to replace it before the car leaved me stranded in the middle of nowhere.

Thanks for your input,

Costas C.