OK, I've about give up on the manuals for wire identification. Things aren't matching according to them.

This is my C100 set-up on the cab side:

1- RD-PNK
2- GRN-BLK
3- DKBLU
4- WHT-BLU
5- LTGRN-YEL
6- LTGRN-WHT
7- NOT USED
8-LTGRN-RD
9- RD-LTBLU
10- BLK-WHT
11- YEL(small guage)
12- BRN
13- PPL-WHT(thin stripe)
14- PPL-WHT(thick stripe)
15- PNK-TN
16-GRY-YEL(small guage)
17- BLK-YEL
18- DKGRN-YEL
19- RD-WHT
20- NOT USED
21- WHT-RD
22- BLU-YEL
23- YEL-BLU
24- ONG-BLU
25- LTGRN-ONG
26- PPL-ONG
27- PNK-GRN
28- YEL(medium guage)
29- LTBLU-BLK
30- BLK-NK
31- DKBLU-PNK
32- NOT USED
33- WHT
34- LTGRN-BLK
35- RED(medium guage)
36- RED-BLK
37- NOT USED
38- TN-LTGRN
39- BRN
40-MEDBLU
41- LTBLU-RD
43- RD(small guage)
44- PNK-BLK
45-NOT USED
46- NOT USED
47- RD-LTGRN(heavy guage)
48- YEL(heavy guage)
49- BLK-ONG(heavy guage)
50- GRY-YEL(heavy guage)
51- BLK(heavy guage)
52- NOT USED
53- NOT USED

Unfortunately I didn't mark the wires off the '90 F250 before removing them from the plug but I can still get the arrangement off the cab sidet that is still intact. I matched what wires I could according to color and size comparison and these are the ones left over on the F250 side in the engine compartment.

YEL(heavy guage)
RD-BLU
BRN-BLU(heavy guage)
BLU-YEL
BLK-WHT
PPL-BLU
PPL-GRN
RD-WHT
DKBLU-ONG
YEL-GRN(small guage)
LTBLU-BLK
YEL-GRN(medium guage)
ONG-BLU

On this set up my tank pumps come on in the RUN positon but shut off when you go to the START position, my hi-pressure pump still does not operate. I'm also getting a sulphur smell from the left A/C vent that I didn't have before this last re-arrangement. That's when I gave up for the day. My head lights now come on when I crank.

 

Close but no COOKIE yet. I got most of my wiring issues straight by ohming them out and following them to the source for verification. So far I only have 2 problems with it so far.
1- My headlights don't come on with the switch but they do come on when I crank the engine(LOL). Supposed to be the other way around.
2- I still can't hook up my inertia wire to the F/P relay. It acts like it opens it back up and voltage drops to 2.5V. I can hook the inertia wire to the RED power wire that's activated by the EEC relay and all systems function properly. Go figure. I was able to get rid of the 87 code but the 95 stays no matter what I do to the system.

Now for the GOOD news. I was able to crank and partially start my engine. It won't start with the throttle closed but WFO it will crank for about 5 seconds then catch, run up to about 2500 RPM then die(but she runs smooth). By the time I got to the point of checking fuel pressure(45psi KOEO) my battery got to weak to crank it again to see what it does while it was attempting to run. It sounds like it runs out of fuel after starting.

 

I found this in my AllData file:
CODE 95 Right air always upstream

All other Code 95 references are to the F/P secondary circuit failure. What is considered the Primary and Secondary circuits?

Could this Code 95 from the EEC cause my fuel system to shut down after the engine starts?

 

I checked the TPS and all is within range. During the short run of the engine my fuel pressure drops to 40psi then goes back to 45psi after the engine quits. So my fuel pressure is good. I advanced my distributor gear by 1 tooth to give me a little more playing room on adjustment. It seemed to crank and start faster when it was fully advanced. So my distributor is sitting in the middle of rotation now. I also removed the SPOUT and tried it and no change.

 

Primary -- the circuits involved in supplying power to the FP relay coil, and allowing the computer to control it by grounding one end (the "FP" signal)

Secondary -- the circuits involved in transmitting power from the battery, through the FP relay contacts, and thence to the inertia switch, tank selector switch, and ultimately the fuel pump.

Think of it like your starter solenoid.

Primary -- the relatively small wires comprising the connection from the battery through the key switch to the starter solenoid coil

Secondary -- the big fat wires connecting the battery through the solenoid contacts and thence to the starter.

 

The computer will not fire the injectors and will drop the fuel pump relay out if it does not see "PIP" coming from the TFI. The engine may fire briefly based on leaked fuel and the TFI "bypass mode".

Do you have spark the whole time it is cranking? Have you checked the continuity of the PIP signal from the TFI all the way back to the computer?

 

Yes it fires all the time. I only did a check on the TFI and the signals in the harness with KOEO and in the START position. So I'm assuming it was checking the signal from the computer. Plus I checked all the engine sensors for ranges. They're the same as the ones on the 302 and voltage is present as required by the manual. I developed other issues today. Now the dang thing is hard to crank. I had the battery checked, replaced the solenoid and starter(was going to do this any but was waiting til I got the motor running). Still hard to crank. I put a wrench on the harmonic balancer bolt and couldn't even turn the engine. I'm sure you know what I was saying. Anyway, I removed the spark plugs and disconnected the coil wire, she spun over normal. I put the plugs back in and she spun good. Then after I hooked up the coil wire and tried to fire her up. Back to hard to crank again. 2 steps back. I can't progress further with other problems until I fix this one now. When I cranked the engine without the coil wire on, that thing fired all the way to the coil mount. So it's putting out good, LOL.

 

I'm curious how the early trucks with the lowpressure in-tank pumps and the high pressure frame mounted pumps are wired. Does anyone have a quick schematic of it?

I know how the later model trucks are wired but I hate to assume that the early trucks were the same with just the addition of the hi pressure pump.

Thanks,
Tim

 

Here is the link that subford put up for the electrical side:https://www.ford-trucks.com/forums/s...d.php?t=476082

Here is the link that subford put up for the DFR description:https://www.ford-trucks.com/forums/s...d.php?t=476686

 

Thanks for clueing me in!

 

They are. I'm installing a '90 351W that had the later style pumps that were on the truck and mine are the 3 pump style. After rewiring my chassis harness and going over everything, the only difference is the omission of the hi-press pump and a wire color change on the F/P relay and the wire from the inertia switch to the selector.

 

did you figure out what was drawing the voltage down with the inertia switch wired in?

 

No not yet. I have the pumps wired on the hot side of the relay to try and get the engine running but now the damn thing is hard to crank. When I quit working on it last night, I disconnected the battery. Then went in this morning to do some more troubleshooting(I burn out easily on the mental side of electricity), I dropped the exhaust to try it to see if it might be restricted(this was a donor part also but cat forward. That thing is almost $300). After hooking everything back up, it started acting like a dead or weak battery. Needless to say, I spent most of the day chasing that issue and never was able to get it start again.

 

You should check out Frederics home made Y-pipe post when you have time. He's awesome!

 

Go figure. I had a hard time turning the engine with a breaker bar. I thought GEEEZZZ, now my engine's froze. I remove the plugs and it turned easier but still stiff, then I said, well figure in new rings, pistons, belt tension and others, it seemed OK. I cranked it with the starter and it was a little slow but started speeding up as I continued. Put the plugs back in, got one start on it and it started dragging again. Did the previous steps again and at least 4 more times while trying to trouble shoot my no run problem. Then the last time I pulled the plugs she spun real fast. Put the plugs back in and it's been cranking normal again.