I have a 1987 Volvo 240. It is manual.
It idles just fine. I can rev it up while it is idling and it sounds great.
If I start slow it seems to work under about 5MPH....basically first gear. Once you push on the gas for real it just doesn't move.
It starts bucking like a mule half the time and it really won't go past maybe 20.
It doesn't smooth out at all.
If you accelerate very very very slowly it is a little better but still I have not gotten it past 25 or so.

All I have done so far is replaced the fuel filter.

Any ideas?

Please remember that I am am mechanic only in as far as I can relate to other problems I have had before and read a Chiltons.

Thanks

 

Is this car new to you? Or have you had it for a while and it started doing this recently?