Hello guys and gals. I have a odd issue that I myself have never encountered and am in the need of assistance with.

1989 Ford F-150 5.0 Auto 2WD
Slightly rough idle, misses through driving range and has a vibration at low rpms while driving.

this issue spurred up all of a sudden. I pulled plugs and #8 was black.
Did full tune up, plugs, wires, cap, rotor, changed coil, fuel filter, and same issue. When I changed fuel filter, it was quite clogged but not to awfully bad. I cleaned front tank before seeing as how i replaced the in tank pump when I bought the truck two years back, so I am unsure why the fuel was so dirty. Rear tank is in-op.

Next I ran a fuel system cleaner and cleaned throttle body but still came up with naught.

today I have ran all self checks, and came up with a PIP sensor code of 211. I then have ran the gauntlet of system checks and cannot find anything that is out of range on a VOM. Went ahead and pulled distributor to make sure PIP was grounding OK, cleaned everything up and put back together. Checked timing ( yes i unhooked SPOUT ) and still have the same issue, ran self checks one more time for fun and cam up with ETC out of range ( code 21)

I have checked every sensor I can think of, would list them all but my head would spin from abbreviations. Any help would make me eternally grateful this is my daily driver.

 

You say the timing stays the same with the SPOUT in or out.
That may be an open wire between the ICM and computer.
If not I would open the computer and see what it looks like inside.

I would change the PIP (stator) in the distributor if you got a code for it.
But you should have 2 digits codes so the 211 does not sound valid.

The 21 code may have been a cold engine.

You can not have two digits codes and three digits codes on the same truck.