Thanks for letting me join, I own a 1.8 rover 200 coup fantastic car drives great but I think it maybe using too much fuel, I am only getting about 350 from a full tank instead of 423, I have no leaks and the tank is dry.
Does it run OK? Good cold starting, but runs a bit lumpy when hot? Sooty exhaust, smells strongly of petrol? If any of these get the temp sensor checked - not the gauge one, the one that talks to the ECU. When was air filter last changed?
If your model has a fuel pressure regulator with a rubber diaphragm, these can leak and allow excess fuel into the inrtake. many of these have a tube connected manifold vacuum to it, and any leaked fuel gets sucked into the engine. Check if your model has one of this type - if so, locate the vacuum pipe (usually a rubber tube ) - pull the end off the engine end, and see if its wet, or smells of fuel. If it is, it needs replacement. Does the exhaust smell of petrol or is sooty?