/Background: 1990 560SEC Euro, had been running somewhat rough, econ gauge not pegged to left as it should have been @ idle, hard to start.

I found a handful of vacuum leaks, around some of the intake ports, the base of the air flow meter housing, and a few lines/hoses. I pulled the intake and replaced all rubber /plastic bits, all 8 injectors, and new gaskets.



I turned the key to prime the system a few times, then went to each injector and loosened the nut to look for fuel flow. A few did not have any, so I tried to prime a few more times, with success, except for cyl #5. I then proceeded to loosen the nut at the fuel distributor, and all had fuel except for #5. I tried to prime a few more times and then saw fuel at #5.

Tried to crank the motor over, and it would sputter, and almost catch, but never really run.

Sprayed some carb cleaner into the airflow meter, and on the next attempt it fired and ran for a second or two, then died.

After reading some other threads, I have turned the 3mm adjuster in by 2 full turns (8 steps at 1/4 turn each), and I think it sounds worse now than before as it tries to fire.

I have double checked my spark plug wires, cap and rotor as well (all are new). Unless I have the cylinder numbering wrong (1-4 on RH side, 5-8 on LH side)...

Not sure where to go next here, feeling a bit frustrated as I was hoping for a nice smooth startup.

Thanks
Andrew