Bad Idle, Low power on 302
 

Went on vacation and my engine overheated, someone left off the radiator cap.(>_<) I saw the gauge maxing out and heard the engine rattling, like any hot engine does. I saw the sign saying "service 2 miles" and decided to slow down and nurse it there. As soon as i let off the accelerator it acted like i cut its throat. It lost power and shut down. I couldnt get it to restart at all for over30 minutes.So I was stuck there until towed, and bought the pre-mix antifreeze, and once i added it, the truck started right up. Idled poorly, but ran.
I get her up to 65 on the interstate and she purred like a kitten for the 3 hoursto my bud's house,and the 5.5 hours back she'd run good at higher RPMs. Just at low speeds or an idle would it sound like it was running on 7 cylinders. I went ahead and bought all new motorcraft plugs and wires, gapped them according to the decal under the hood,(.052 - .056) and swapped them all out. Still no difference. Checked for cracks in the distributor cap, none. It acts like it jumped time, when you push the gas pedal it acts like it wants to go, but its held back. Now before I go buy a compression tester and a timing light, anybody ever come across such a problem?
I've put some seafoam and drygas in the gas and let it run a while to be sure it wasn't water in the lines. All the plugs look clean and firing very nicely, just about perfect. has 125,000 miles on it and cant afford to lose a motor thats been this durable for me. She's a 95' f-150.
A few have said burnt exhaust valves, some said blown head gasket, one even said buy a fuel lead substitute additive and run it through before anything. If ya got a good suggestion as to what to do before I try and pull the heads on this thing, (worried about the exhaust manifold bolts), any suggestion would be helpful.

Included is a picture of the "Green Mountain Boys" , "Old Blue" is the one with the problem.

[IMG]local://upfiles/11181/1DA007E414F04163ACF7945BAB7A7D32.jpg[/IMG]

RE: Bad Idle, Low power on 302
 

Update, she idles nearly smooth, hardly any valve clatter at all, barely audible unless your trying to listen for it. I've just unhooked the battery and will wait a while before I hook it up again. Maybe the computer needs an enema I dont know. Also went through the electrical plugs and gave em some wd-40 and some dielectric grease in case of water or corrosion, to no effect so far.

RE: Bad Idle, Low power on 302
 

Hopefully no rings were damaged, but if it's idling that's a good sign.
Did you drive it? If so, did it still have some power?

RE: Bad Idle, Low power on 302
 

Took her out and dropped her down, she took off, but hesitates at first and then takes off. She acts like its out of time but dont see how overheating would make it jump time. Do you know if this has an OBD1 or OBD2 system?