2000 Volvo S80 with 84k 2.9 (non-turbo) I bought the car this was, after it warms up the car feels like it is starving for fuel but never stalls, after driving it for a few miles at say 40 mph and then you slow down and try to speed up is when it feels like it is starving for fuel. The gas gauge dosn't work either and the miles till emply shows ___.___. Could this be the fuel pump or the throttle body and are this two seperate issues? After it starts doing this the service lights comes on but no check engine light!

 

You could also have a plugged cat converter for the starving issue.
There is 2 sending units for the gauge.

 

Thanks, is there a way to check the cat converter and where are the two sending units for the gagues?

 

The best way to check the converters is when it is acting up after hot remove the front O2 sensors and take it for another drive. If it drives fine put them back in and see if it drives bad again. If it does the cats are bad.

The sending units are in the top of the tank under the rear seat bottom.
Also pay close attention and see if other things in the rear of the car do not work.(Rear door locks ETC)