No fuel or RPM

[DGG]

I have an 08 140. everything is working except RPM and Fuel gauge. They went out at the same time. Have checked all in line fuses connections etc. Ignition switch problem?

 

[johndd]

The feature you're talking about is over-run cutoff. When the engine is not revving to provide drive to the wheels, the fuel can be cut off, and the engine kept turning over by the wheels driving it back through the drivetrain. On my Vectra (which has a instant fuel consumption option on the trip computer) you can see this cutting in whenever you lift your foot
in any gear to provide any sort of engine braking.The consumption when the throttle is lifted goes to around 2-3 l/100km when travelling along the flat. Down a hill when the car starts to over-run, it drops to 0l/100km until you touch the throttle to accelerate again. I'm not sure which other cars have this feature. The 4cyl Camry I hired last week didn't seem to. At least that's what I surmise from the fact that after 900km of country driving it had used 75 litres of fuel. (8.3l/100km) which in my opinion is hopeless. I remember Dan getting something like that (or better) from his 5.7 VX SS. The Vectra gets 7l/100km on the same trip.