I am having so much trouble with my Volvo.
Last month I replaced the Fuel Filter. A week later my Volvo started surging, making the car undriveable. I got some suggestions that it could be the FPR. I ordered a used FPR and slapped it in and it didn't fix it. One of my fuel pump relays stopped working also so I bought a new one. I put it on and it still doesn't work. does anyone have a suggestion as to what can be causeing this. Thanks in advance.

If your car is not idling right try unplugging the mass air meter, If the car runs better with it unplugged replace you air mass meter. Tell me how that works out for you.

Don't forget the in-tank pump problem.... if the in-tank pump, OR, the 1" long piece of fuel line that connects the pump to the fuel pick-up is bad, you can have poor engine operation. You need to chk. to see (hear)if the in-tank pump is running at all. Tom

I recommend a couple of cans in a row of Techron or some type of high quality
injector cleaner. You use one can per tank. Run a couple of tanks of cleaner
one after the other and see how it runs. Many times if the fuel filter hasn't
been changed in a long time you disturb a lot of crap that the filter doesn't
catch. Usually a couple of cans of injector cleaner takes care of the problem
If it doesn't then you may have more issues to deal with. One time the disturbed
crap was so bad it clogged my injectors. I replaced them all and was fine.

Dave 82 242ti 282k mi.