1990 volvo 740 wagon shuts off while driving

Could be the battery, starter, or neutral safety switch.

chk the fuse for the fan.

For a 1990 Volvo 2.3 SOHC B230 at 700-800 rpm 12 degrees
at 2500 rpm 21 degrees plus or minus 1 degree

For a 1990 Volvo 2.3 DOHC 15 dergrees BTDC

For a 1990 Volvo SOHC turbo same as SOHC specs

no you dont

sounds like a broken wire, but i cant say where, on ignition, fuel pump, under dash, quik scan could save alot of time an money

Go to an auto supply store like PEP boys or Advance Auto, etc., and buy a Haynes Repair Manual for the 740. You may be able to consult one at your local library for free. Even if it doesn't cover your model year, the replacement instructions are pretty much the same for all years. in fact even a 240 Volvo manual would be essentially the same. Pay particular attention to the installation instructions....you have to slide the pump on, and then rotate it a few degrees clockwise to make the upper o-ring seal. Good luck!

Fuel Filter yes! Then ck fuel pressure. But it may be a Converter.

You may have to bend the conections on the fuel pump relay, so they fit tightly. Try gently twisting it l/r, while turning the engine over.
Hope that's it.

Replace your fuel pump relay,this controls the power to the pumps.

Check you're ground.