Hey I just registered and this is my first post. I bought a 1986 f150 4x2 with a 4.9L a few months back. I’m having a terrible time with the feedback carb on this truck. It is running way lean. I made some adjustments to the timing a few weeks ago and drove it about 6 miles and stopped because it didn’t seem right. When I opened the hood my exhaust manifold was cherry red. So I bumped the timing up a few degrees because I assumed it was too retarded causing the manifold to cherry. So bumped it up a few degrees and it runs about like it did when I bought it. VERY ROUGH. So today I decided to pull codes just to see if the ECM has anything stored. I got code 18 and 21. Code 18 is for the spout wire. Upon checking it out I found the wire had a huge open spot, so I cut it and fixed with a butt connector and now it won’t start. I’m thinking it’s too advanced and now the spout might actually be working now so it might be adding more advance and not allowing it to start. I’m sorry for the long post. Lastly two weeks ago I took out the bolt that holds the air hat on and put a piece of threaded rod in its place just deep enough to hole the choke open. The automatic choke always came apart and closed intermittently. I’m very frustrated because none of the places I have been looking have very good information on this type of carb system. I don’t need it to be perfect I just need it to work decent.

 

Welcome to FTE....

With the Spout disconnected, set your timing to 10 deg btdc.

Fully warm the engine before running Self-Test, could be the reason for the Code 21.

Engines are easier to diagnose over the internet when all the codes are listed, and in order of test.
KOEO - (O) Self-Test Codes = ?
KOEO - (C)(CM) Continuous Memory Codes = ?
KOER - (R) Self-Test Codes = ?

 

Yes, in that wire you fixed, there should be a strange looking connector called the spout connnector. You have to pull this connector to take away timing control from the computer so you can set the timing. Find this connector/jumper and pull it out, and then see if it will start. If it does, leave the connector out and set the timing according to the sticker on the radiator. Then plug the connector back in to give timing control back to the computer.

 

That wire is where the spout connector was. It was damaged on the inside, that fix is only temporary. I actually work at the factory that makes most of fords electrical connectors so I am going to get one and fix that wire properly.

 

However you want to do it. A simple male/female spade connectors would work. Just something that you can plug in and unplug to set the timing, and also will not short out if it touches something metal on the engine.

 

Have you closely checked for vacuum leaks?

 

I'm no expert on this but disconnecting SPOUT may let you start the engine, I was searching about TFI for a problem I had and found some good info. See the following link.
https://www.merkurencyclopedia.com/EEC-IV/spout.html

Good luck.