1972 W117 280SE 4.5 Fuel Injection Trouble

Car been sitting around for 3 years. Finally got the engine to turn just to find out the four middle electronic fuel injectors are either not getting or, not providing the injectors with electricity. Figuered that out by
switching spark plug wires, fuel injector fuel leads, and fuel injector electrical leads between the hitting and non hitting cylinders. I see the electricity comes from the bottom of the distributor and cleaning the plug has not helped. Any suggestions besides "Junk It!"? This is a daddy/son project that I took up and its been fun. Obviousley, the sonny boy would be very disappointed if his dream of going for a ride in the old junker is squashed. In advance, I like to thank you for your advice.
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Cleaning the connecter does not fix anything. That plug is for the trigger points. You need to remove the trigger points and inspect them for oil on them. Unsnap the dist cap, remove the rotor, remove the black cover on top, put back the rotor. Look around the top edge of the dist for a notch. That is the #1 to fire index mark. Now get wrench and put it on the power steering pulley nut. Turn it clockwise and hopefully the engine will rotate also. If not, then you will need to hold the belts tight. If it still does not turn, remove the spark plugs. Rotate the engine until the rotor points to the index mark. Now look at the crank pulley, the timing mark should be at O. Move it to O if it is close. Now you need a 5mm Allen socket with a 12" extension to go down the left side of the dist to remove the bolt holding the dist in. Put grease in the head of the bolt so you don't drop it!! Now lift up the dist. The rotor will turn to the left as the gear clears. No problem, just remember that it has to be turned left when you put it back down so it lines up to the index mark when it seats. Now lay the dist on the engine [green wire is still connected, if the tie straps are still behind the power steering pump, cut them] and remove the 2 screws holding the trigger points on. Pull the point assembly out. There are 4 sets of points. Usually they have little clear plastic covers on them. Look carefully at each set. Open and close them and see if oil is on the points. Look in the dist body and see if oil is in the bottom of the housing. If yes, your dist is worn out and not repairable [I have tried to repair them for this problem by removing the shaft and installing an O-ring to stop oil migration up the shaft but it does not fix it]. If the trigger points are oil covered, replace them. Think about a new dist in the near future but not right away, they are BIG $$$$.
If the points are perfectly good and there is NO oil in the dist, then you have one of 2 other problems: either the harness has rodent damage especially where it goes thru the pass side firewall or the ECU brain has 2 failed circuits.
Since there are 4 trigger points and 8 injectors...... the injectors fire in pairs. 1 + 5, 2 + 7, 3 + 6, 4 + 8. Your cylinders are laid out like a Ford: pass side front to back is 1,2,3,4. Drivers side is front to back 5,6,7,8 Your middle dead ones are 2 + 7 and 3 + 6 in pairs. The trigger points send the signal back to the ECU to fire the injectors.

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