Help, got a 97 that runs great with more than 1/2 a tank of petrol. As soon as it goes below 1/2 a tank all hell breaks loose. Get every error message possible (poor engine performance, engine fault, traction control, etc.), runs super rough and stalls out not wanting to start up again. Fill the tank all the way up and bingo, life is great again. I have no idea when the last time the fuel filter was replaced.

Any ideas???