I have a 92 F-150 5.0l 5 spd Flareside with 147,000 miles I bought off the lot new.
The engine runs really good and has been maintained well. Recently, a slight spark knock has been occuring on uphill acceleration. I usually use mid grade fuel but lately have gone back to 87 octane. I decided to check my base timing to see if it was correct.
And so, the same problem I had last timing check presents itself again.Keep in mind this truck runs good but for the ping with 87 octane.
When I run the timing procedure, the truck is at normal temperature. I pull the SPOUT connector and it will not start. If I replace the SPOUT connector and start the engine then remove the SPOUT it dies imediately.

Now follow this craziness...I can start the engine with SPOUT connected, pull my solenoid START wire off(at the solenoid), then remove the SPOUT connector and it keeps running at base timing!

I am not trying to fix what's not broken but my morbid curiosity dictates this is not right and I'd like to know why.

I believe my module is a "push" start not CCD.The 4th pin shows battery voltage at START.
A couple of years ago I ran a recommended procedure to check the harness shield wire for chaffing in front of the computer plug. I didn't find any issues at that time.
Also, Ive never really determined where the 22,000 ohm external resistor is for the IDM circuit.Again, just would like to know.

ANY thoughts will be appreciated.

 

Have you ever tried changing the module on the distributor? This is a guess, but the module is supposed to run the engine in a limp mode of sorts by itself without the computer's help. It sounds like it can't do it since it won't run without the spout.

 

You are saying it starts fine with a cold engine but will not run or start with the engine warmed up unless the SPOUT is removed. Then it has a slight spark knock while running with the SPOUT removed.
My guess is that you need to replace the crank damper as it has moved and then re-time the engine.
You are trying to run the engine out of time.

This is the way it is suppose to work.

 

The truck runs great hot or cold rain or shine. You cannot start the truck with the SPOUT disconnected. If you crank it first then pull the SPOUT it shuts off.
The weirdness is the only way to get it to run with the SPOUT disconnected is to:
-Start the engine
-pull the solenoid START wire off of the solenoid
-unplug the SPOUT
All I'm trying to do is check base timing... just check. That's all.
If I do as stated above I can indeed check base timing.I then shut down the engine, plug everything back just like normal crank up and drive away.

Pulling the solenoid START wire to keep it running while the SPOUT is unplugged is not normal.

The module is original.

 

The start wire from the solenoid is only hot while cranking.
Sounds like the solenoid is not wired right or wrong solenoid or bad solenoid.
As soon as it starts the start wire should be the same as an open (the same as if you pulled the wire off).

 

With the START wire disconnected from the solenoid, it is receiving 13 volts from the harness side, read on a digital volt meter. However a test light will not glow when hooked to it... With a load on the wire the voltage drops to zero.

 

Last year i did a tuneup on my 96'. Afterwards everytime i would go up a hill it would develop a really slight miss. Checked everything i could with my voltmeter...nothing. Took it to my mechanics shop and a few hours later he called and said it was fixed. Walked in and he handed me a broken sparkplug and told me next time be more careful. Cost me $30 but it was worth it.

 

Thanks for your reply. Any thoughts help.