My 94 850 GLE that I have just recently bought, runs and drives perfectly, but it seems to be very bad on fuel. It only does about 250 miles for a 70l tank of fuel.

I checked the diagnostic codes, and all are reporting 1-1-1. The car has the Fenix ECU and is a 10v 2.5 engine. The car has 129,000 miles but the engine was replaced by Volvo main dealer only 20,000 miles ago but this was 2005. The old guy I bought it from didn't do much mileage since it was replaced.

I'm going to give it a service, replace oil/air/fuel filter and the plugs, but the car just runs so well, I doubt its something as simple as that.

Any other ideas why I'd be getting bad mpg?

Thanks

Steve