I’ve got a 94 f350 460 5 spd 56k. One day hit a bump it just snapped and went haywire barely running checj engine light and using twice the fuel. I cannot connect to the computer with scanner, I have checked fuel pressure, both tanks seem good, fuel volume good, gutted converter, fuel reg-cheap,air charge sensor, ign module, all no difference and has ran crappy every time since.I saw the thread about caps in the ecm so I pulled it out and two had one burnt leg, almost if not gone and one seemed ok? I went to tv shop and got three 47 u 16 v caps and replaced them. Put it in the truck and omg it ran great for about three to five mins. It has not done that since the trouble, but as it was idling, seems as if something clicked and went right back to crappy. I pulled the ecm, solder looks good but noticed duh after looking at the post, maybe that one had a different size? All of the orig are gone. Could this be it? Could you advise me before I pull all of my hair out?

 

You could have taken out the caps as they need to be of a much higher voltage rating than 16v.
You should have two caps of 47uf 20% @ 25v & one at 10uf 20% @ 63v.

My last order for the caps, note my order was to more than one PCM.
Attachment 285063

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Subford nailed it and I'll offer that any (and I mean any) soldering on EECs (unless you're a NASA Cert Solderer) can introduce problems later.

 

I doubt that any amount of speculation about the ECU will solve this problem.

You hit a bump. This does not cause capacitors to fail. Sure, you found leaky caps and replaced them, but the symptoms continue. Capacitors fail from age and heat. Yours have had almost 25 years use, so this is no surprise.

Subford as always is correct, the correct capacitors must be used. 16V rating is marginal, but sufficient. Using a 47mf in place of a 10 mf is not advisable, but I don't think this will create the problem described.

So, back to the original post. You cannot "connect to the computer" like you would in an OBDII equipped vehicle, but you can try to read codes. This takes a simple jumper and you need to read KOEO, KOER, and CM codes via the check engine light. Your light is on, so there will be codes. The engine is running, so the ECU is at least partially functional.

You have checked fuel pressure. This is good. You have replaced ignition components, also good, but fuel and ignition issues may not create codes, (which you have). You will find codes that point to various sensors either not functioning, or not functioning within limits. Unfortunately, your EECIV equipped truck does not support commonly used applications like Torque and reading live operating data requires equipment not everybody has. Early EECIV did not support even this rudimentary diagnostic step, so you must rely on hard failure indicators to guide you.

So read codes and post them up. Hopefully somebody can help. and good luck.

 

Take a look at the pictures of the circuit board on this post. It will show you what the proper values are. I replaced mine, but I have experience in circuit board repair. https://www.ford-trucks.com/forums/1...eshooting.html

 

 

Awesome that it's working well!

 

The EECs are not complicated, and the capacitors are simple through-hole components. Pretty much anyone with even the slightest of soldering skill can easily replace the capacitors.