Hi there, I just joined this forum and hope I can solicit some help and advice from you.

Quick intro:
we purchased a 1992 E250 4x4 Sportsmobile in September.
She has the 5.8/351W engine which is a rebuilt replacement engine with about 30,000 miles on it.

She has this occasional hiccup:

idles very irregular and sometimes too high, sometimes too low.
When driving, it feels like she chokes every 100+ miles or so (= rarely), to the point where she'll almost cuts out / misfires completely.
When just sitting and idling, the engine has just simply stopped twice now during our trips. But then starts right back up.
We did distributor, caps and rotors, plugs and wires, along with the standard maintenance (filters, fluids etc.) and added a MSD module for better fuel economy.
Our go-to car mechanic thought it might be an issue with the ignition switch, but that is fine. We had all aftermarket wiring for stereo / alarm / CB etc. cleaned up and rewired to the battery rather than the ignition, but still can't figure it out.

Any thoughts? I am afraid I don't know much about engines, but I would love to learn more so we can get this old lady off road with no concerns whether we make it back home....

Thanks!

Anette

 

I would start with the EEC self-test to see if it's complaining about anything. If you don't have experience with this, you can take it to your local auto parts store where they can read it for free.

There are a couple of sensors that you can check:

Throttle position sensor:

https://www.ford-trucks.com/forums/1...ed-update.html

Oxygen sensor: If it hasn't been changed in 100,000 miles it (they) should be changed.

Fuel pressure: You will need to get a pressure gauge to check the fuel pressure at idle and under load. When you say you changed the filters, was the fuel filter changed as well? Again, more than 100,000 miles on it, it should be changed.

I think that year may still have the TFI ignition module screwed to the distributor, where a lot of them overheats and can cause running problems.

Other than these, I would chase down whatever else the EEC self test shows up.

 

Thank you so much for your advice, it's greatly appreciated!

It's good to know where to start, and I'll keep you posted on the progress as soon as we start working on the old lady.

Anette