Solved Barely running Sounds like missing cylinders Code DTC 513 and many more

[yostyexplorer94]

I left work and stopped to fill up at the gas station. Shut my 1993 explorer off and filled up. When I started to leave, it barely started and was running terrible. I pulled each plug wire to see if there was any notice change in idle. Looking under the hood, the back left cylinder made a different noise when unplugged. The rest didn't make much difference. I drove it home and had to let off the throttle every time to get it to shift into overdrive.

The next day, I fired it up and it ran somewhat ok. Drove it around and it still was not right but it was running better. Shut it off and restarted. Ran worse than the day before.

I pulled the codes.

Thanks to the explorerforum, I looked up all the codes. 513 stuck out the most. The couple of threads I read through had information saying the pcm has capacitors that have failed. I was fortunate enough to have a parts explorer sitting there with the right pcm in it. Swapped them out and it solved the issue. So far it is running great.
I wanted to share this experience so if anyone else gets codes like these, they have another thread to read to help.

Photo of good pcm. Capacitors look good.

Bad PCM with bad leaking capacitors. One leg of the capacitor wasn't even making contact anymore

 

[ChildIdenticant]

+1 to this affirmative evidence. Have seen on other ford forums and other make forums for aging vehicles. Don't know why the photos haven't shown up on this forum .

went to junk yard 2 days ago, pulled an airbag controller for a 92 town car. entirely black and bubbled around the base of all electrolytics on airbag controller. disgusting.

Those caps are dying. they are in the pcm. they are in the abs controller, they are in the speed control amp, they are in the chime module, they might be in the 4wd controller ( I don't have that, can't confirm).

Electrolytic caps have been dying for at least 15 years. Replace them with high quality supply before they eat your boards,

 

[wwhite]

I'm in the process of installing new caps as well.
Your 'good pcm' has leaky caps, you can see the brown ring, unless you spilt drops of coffee on them.
I circled the bad caps on your good pcm:
Looks like water stain.

 

[donalds]

Time for new caps

 

[ChildIdenticant]

Let's not mislead. Electrolytic caps can be bad even without clearly having leaked. I haven't opened much autmotive electronics, but have worked on much AV equipment. The only decades old commercial/consumer devices that I have seen that have consistently stood the test of time are sub 13" panasonic/national/matsushita/ crt's that used genuine panasonic caps.

This is a board from another 92 lincoln that is not near the worst I have seen:

If you look at other vehicle forums, more relevant photos can be seen. And it is effecting post millenium vehicles . Crap electolytics effected a lot of equipment in the early 2k. But those tended to explode.
Swap your caps before they leak. Lot easier if you do it before vias are harmed.

 

[donalds]

An example of my caps
Pic I took a few months ago

 

[wwhite]

An example of my caps
Pic I took a few months ago

What computer is that? Those look like industrial caps, lol, heavy duty anyways.
The black thing, is probably a 'Varistor', protects the circuit from voltage spikes.

 

[donalds]

Its the pcm from a 98 sport.....my spare

 

[yostyexplorer94]

I'm in the process of installing new caps as well.
Your 'good pcm' has leaky caps, you can see the brown ring, unless you spilt drops of coffee on them.
I circled the bad caps on your good pcm:
Looks like water stain.
View attachment 426088

I did notice that. I should have said working and non working instead of good and bad. I had to verify the pictures with the bad pcm to distinguish which was which when it when I posted the pictures here. The plan is to repair the bad/non working one and swap back in.