Just thought I would post some info on the ECM capacitor replacement issue. I have a 1993 F350 reg. cab, 7.5, 5 spd. 206K miles. I bought this truck new so I know this truck well. My symptoms. Hard starting, fluctuating idle, fuel starvation at lower rpm. (WOT was ok) These symptoms have progressed over the last few years. After lots of diagnostics on the entire ignition and fuel delivery systems, I went ahead and replaced the following parts without much improvement. ( with 206K I figured they need replaced anyway) MAP sensor, TPS, IAC valve, coolant temp sensor, air change temp sensor, fuel pressure regulator. I also replaced plugs, wires, cap/rotor a few years ago. Checked and fixed any vac. leaks. The CEL never came on during all of the issues I had.

After all of the above improvements, I still had the symptoms. I jumped on line and researched the ECM in these trucks and came across a few articles on bad capacitors in the ECM. I read where the 3 capacitors will fail after 15 plus years and will greatly affect the performance of the engine. I found exact symptoms in relation to what I was experiencing. I pulled my ECM and inspected the 3 capacitors. They were not swollen or leaking like most others I read about but I also read where they do not have to exhibit physical failure to be bad. Mine were 30 years old so I went ahead and ordered them on Amazon and replaced them. INSTANT! improvement. My truck now runs better than it has in years. The capacitors I replaced were, (2) 47 uf 16v and (1) 10 uf 63v. There are lots of videos on You-tube on how to do the actual de-soldering, removal and re-soldering procedure.

So, if any of you have exhausted all other attempts to correct any of the above symptoms and still have issues, look into the ECM capacitors. It's a very inexpensive procedure and could have profound results.

 

Thanks, That's precisely why I wanted to post it. It can be very frustrating trying to track down problems on these trucks.