Hi there I'm helping a buddy get his 87 244 running again. It has been sitting for a couple years. For starters, the fuel line between the pump and filter was kinked, the fuel line from the rear of the filter was torn, and the internal sender unit/pump/filter was shot. (rust in tank). I replaced the pump, filter, sending unit, and cleaned out tank. Relay is good. I have not messed with the injection system much, so I'm not sure where to start troubleshooting from here. The engine turns over, and sometimes sputters for a couple seconds making us believe it's going to run, but it seems like it's still not getting enough fuel. What are some basic starting points for trouble shooting the fuel injection? Thanks! Oh, the FPR has been replaced as well.

 

Test fuel output after high pressure pump under teh car. Then work your way forwards from there.
Did you replace the main filter near the pressure pump, or just the in tank sock filter?

 

I replaced everything from the in tank sensor unit (pump and filter and entire unit) to the main pump/filter unit, and it is expelling fuel from the main fuel filter to the engine, so the problem lies somewhere in the injection system.

How do you know? Did you pressure test the fuel system? Flow and pressure are two seperate things. You need to check fuel pressure at the fuel rail and check the ECU for codes if that model is so equipped.