I have a 1990 f150 I-6 5speed 80k. the truck starts to lose power around 2000 rpm, check codes , nothing shows up comes back with the pass code 11. put timing light on truck and accelerate the timing is not advancing.Spout connector is pluged and does check good. truck runs the same with in or out. Looks like a possible pcm replacement but wanting to here input before I go buy I new one.

 

You need to UNPLUG the spout when setting timing. When my pcm went out it only ran with the spout unplugged. Goodluck!

 

Check for continuity in the SPOUT connector itself and also between the TFI module and the computer. If sounds like either the SPOUT connector itself is not working, or there is a bad connection along that wire between the ignition module and the computer. Bill (subford) may come along with a wiring diagram for you if you're patient...

 

1990 4.9L (VIN Y) engine.
Here is the Ignition Diagram for system "D" Push Start:




PCM # FUNCTION Wire Color
16 IGN GND ORANGE/red
56 PIP A GRAY/orange
36 SPOUT PINK
4 IDM TAN/yellow

ICM # FUCTION Wire Color
6 PIP GRAY/orange
5 SPOUT PINK
4 START RED/blue
3 ICM POWER RED/LT green
2 COIL TACH TAN/yellow
1 GND BLACK/LT green

/

 

the spout connector is working, I set timing and when I plug the spout back in the timing advance about 5* I also did the timing advance test through the computer where it will advance the timing for 2 minutes. it did advance about 20* but only for about 45 sec not 2 minutes then it settle back to where it started, but it still will not advance when you increase the RPM but it will move for a second on deceleration and sometimes on acceleration but it always settle back to where it at idle no matter if you hold RPM up.

 

Are you checking it while the computer is still in the self-test mode?