Edit: You should check the fuel pump relay first. They commonly go out on the 240 series and will cause intermittent stalling problems that get worse and worse over time. It's located above the passenger side floor board. You can find YouTube videos showing how to replace it and it's a fairly cheap part at most auto parts stores.
You are a bit brief on your description but I'd start with the most obvious items first, which would be fuel. Are you out of gas? I know this sounds stupid but the gas guage does not always read correctly on a 20 year old car. Also if you run on empty often you do suck up gunk that has built up over the years and this can clog the fuel filter and basically choke off the fuel supply. The car will start often but if you go over 30-40 mph the car will hesitate because more fuel is needed at higher speed and the filter just cannot pass enough through because it is dirty. Next I'd check the mass air flow meter. It is right behind the battery and has a big plug on the top of it. If you can start your car and then unplug this and the car still runs then the mass air flow meter is broken. It controls the air/fuel mixture and your car will run like crap without a working part.
Update From denverdriveby 11/21/11: I just bought a used 1986 Volvo GL 4 Door Sedan with automatic transmission with 155K miles that had this problem. Here's how I fixed my problem and all of you out as well:
first things first, all cars have similarities and differences and just because something worked for me doesn't guarantee that it will work to fix your car's issues.
My car was bought used. I am probably the 3rd or 4th owner. The interior was trashed but body was in good shape other than missing some door trim pieces. The previous owner changed the oil dutifully every 3months or 3000 miles but had let the rest of the car basically go to hell (and it showed) but I bought it cheap and the motor and trans worked fine other than this annoying (and sometimes scary) intermittent stalling problem.
I noticed that the wires coming off the ignition coil (located driver's side fender wall) to a dangling fuse had a wire that was partially melted. I thought nothing of this and wrapped some electrical tape for a temporary fix until I could solder in a new wire thinking I probably had a relay or fuse out somewhere. I honestly thought I had a partially plugged up fuel filter and fuel pump so I went ahead and replaced both of them. The stalling problem still persisted though. I went back and soldered in a new piece of wire to replace the melted piece that connected to the positive side of the ignition coil. Voila! Problem solved! A few hours after I fixed the wire, I noticed that IPD sells a ready made kit to replace this apparently well known problem: http://www.ipdusa.com/products/5731/102452-watertight-fuse-holder I wish I would have known about this part before I wasted 30 minutes outside in the freezing cold soldering!
I am fixing this old car up to the point where I can drive it across country so to be on the safe side, I also replaced the ignition coil and will replace the fuel pump relay in the next few days. These are items that are low cost anyways and anyone who wants a reliable car would be wise to replace them. I would strongly suggest if you are considering buying an old 1980's/1990's 200 series Volvo that you want to be 100% reliable and breakdown free that you replace the following parts:
Basically, forget all the wannabe mechanic's advice on what to check and check your ignition coil wires looking for burnt or melted wires. If you see any signs of melting or burning, do yourself a favor and buy the IPD wiring kit for $15 or if your a cheapskate like me, solder in new wires. Always remember that some OTHER problem led to those wires melting so at this point you really need to look at replacing the Bosch 5 pin fuel pump relay underneath the glovebox and to be safe, the ignition coil as well. A really smart person would suck it up and replace the fuel pump and filter along with your standard tune-up / maintenance stuff to ensure another 20 years of legendary Volvo reliability
hope my story helps!
long answer: yes
Yes the 240 does have fuses. Was that your ?.
how do adjust timing belt on a volvo 240 DL ?
how do you reset engine light on 1991 volvo 240
1981 240 volvo #5 fuse blow when i try to start the car....
YES
Yes I believe actually the 1986 to 1992 Volvo 240 4 doors are all interchangeable parts but I'm not sure for 1985 and earlier models.
240 Diesel
Which sensor ???
If they're identical, yes. Try it and find out.
it turns clockwise. Firing order of Volvo 240 w/B230 1342
four