I recently bought a 93 F150 4wd with a 4.9l and 5 speed. I thought I'd give it a tune-up last weekend, so I changed plugs, wires, cap, rotor. The old plugs turned out to be worn pretty bad. I had to remove the old distributor to get the cap off, so when it was all back together I reset the timing. Now I've got a noticeable misfire at idle. There is a chirp sound each time it misfires. It's pretty random.

I checked codes and I'm getting a couple. The one that's throwing me for a loop is #213--Spout circuit open. The spout circuit is not open!! I even cut the wires going into the spout connector and spliced them together incase there was a problem with the plug.

The timing advances from 10btdc to around 20btdc when the spout connector is in. Obviously the spout is closing. Also, the timing moves around a little with the spout connected. I do notice that when it misfires it also retards the timing a few degrees at the same time. The timing light still picks up a spark every time, but its a few degrees behind just for that split second.

I tried replacing the tfi module with no change. I'm hoping it's not the computer. Anyone else out there experience this? I'm also getting 172 or 173 (lean or rich) each time I do KOER. 173 (rich) shows up more than lean. Any thoughts?

 

You need to verify continuity between pin 2 of the TFI Module and pin 36 of the PCM. That is the path for the SPOUT circuit. In some cases the TFI Module can short out the signal which causes this error. Seeing you have already changed it, you need to verify the signal path. Also look for signs of the shield wearing through the wiring. This will also short the signal.

 

Thank you. I will try that next. Pricing out the PCM it looks like it could cost $200-300, so hopefully it's just a break in the wire somewhere. I think I might have really messed up because I reconnected the spout connector while the engine was still running. That could prove to be a pretty expensive mistake! It starts right up and runs mostly pretty smooth until the idle drops. Then it starts with this random miss. Thanks again.

 

It is not a big issue to reconnect the SPOUT with the truck running. Personally I do shut off the engine, but many trusted sources state they never had a problem doing it.

 

You might also check the PIP sensor for the misfire. It's inside the distributor. I've never done it, but I hear that when they do need replacement, it's much, much easier to just buy a new/reman distributor than it is to replace the PIP sensor.

 

Code 213 is SPOUT Circuit open. A bad PIP would not typically trip that error code. PIP issues usually trigger codes 218/222. The circuit open description means the PCM is not seeing the proper signal. That can be from a true open or in some cases there is short circuit to ground.

 

Okay, I finally got a chance to check for continuity between the spout terminal on the ICM and pin 36 on the harness side of the PCM plug. Continuity seems to be perfect. Showing 0 ohms. I'd really like to try a different PCM without spending $250 at Autozone. I only paid $500 for the truck!! Gas mileage has definitely been suffering which I believe is because the PCM isn't advancing the timing properly. I wonder if there are any resistance or voltage checks that will determine whether the problem in the spout circuit is the computer or not. The TFI module I put in is brand new from Autozone. I'll see if there are any checks I can do to that. I know that occasionally you can get a bad part out of the box, but I doubt that it would have exactly the same problem as the one I replaced. You never know. Thanks again for the help.

 

Measure the continuity of the SPOUT circuit to ground. The shield around the cable bundle may have worn through to the wiring. There was a Tech Bulletin issues about that one several years ago.

The Haynes Manual has a great write up for checking this circuit.

Next question...what color ICM did they sell you? It should be gray.

 

I'll go check that short to ground right now. The ICM is grey. Thanks again.

 

Okay, I'm showing 641 ohms between the spout wire and ground. 719 ohms with the ICM unplugged.

 

Just checked Haynes manual, resistance to ground should be greater than 10,000 ohms. This is probably the problem......along with an airhead of an operator!! I'm not sure why I didn't see this check in the manual before. I'll report back after I run my own wire from plug to plug and recheck. Once again, thank you.

 

Glad to hear you found something. I'm sure you will get it repaired soon. Great find!

 

Well, running my own wire didn't work. It still runs the same. Like usual I got ahead of myself. After this didn't work, I went back to the manual and the resistance should be 10,000 ohms with the PCM unplugged. I didn't have it unplugged when I checked. I'll go back and check resistance, but I'm thinking if that was the issue then it would have cleared up with the new wire. The new wire is not hitting any ground anywhere, and I'm still pulling code 213. It's looking more and more like the computer. Anyone out there have any luck with a junkyard PCM?

 

Stick with it, you will find the fix for the problem.

 

Yes I have had good luck with the ones out of salvage yards and from what others have said they do not have much luck with the ones from auto part stores.

You can buy about six from a salvage yard for the price of one from a auto parts store so if you get a bad one from a salvage yard take it back or just buy another one.

It seems a lot of the the time the problem the PCM was sent in to get repaired is still there when they resell it.
I think they just look them over and if everything looks good they just replace the Caps.

However your problem does not sound like bad Caps.

Your problem most of the time does turn out to be a bad PCM and that is why I have stayed out of this thread so far as I hate to tell someone they have a bad PCM.
I have heard that 85% of PCM computers that are sent in for repair that they find there is nothing wrong with them.
So if you replace the PCM and the problem is still there you will know that the PCM is not your problem.
Then you will have a spare test Computer so you can find out if the PCM is a problem on down the road when you sub it out. I keep two spare PCM on hand for my truck tested and read to go.