Looking for a little advise . . . . .
I have an 04' F150 Supercrew 5.4 4wd . . . . Truck had a weird miss (pretty severe at times), at low RPM under load or at idle so I replaced the spark plugs, air filter, cleaned the Mass Air Sensor, and coil boots and it almost went away, the only time you could feel it was at 1500 rpm's or less under an extreme light load (almost sounded like it would ping, wied rattle and you can feel it start missing), but the truck ran fine throughout the rest of the RPM range.
A few days ago my battery took a dump so now after replacing the battery the thing barely idles at all, dies pulling into my driveway, and runs horrible at 70 mph running down the freeway, shaking badly, and the computer has dropped my MPG by 4-5, etc, etc . . . . NO Service Engine light.
I don't get it, no codes, I have put maybe 50 miles on it since replacing the battery and it barely idles and randomly will completely fall on its face at freeway speeds and feels like its got a flat tire. I know the Ford dealership is just going to throw parts at it until I either go broke or they fix it and without it throwing a code on a missfire cylinder I don't want to replace all the COP's to the tune of about 300 bucks and it not fix it . . . . . . .
Thoughts, I am going to try and scan it tomorrow again, but I thought I would see what ya'll think. Run intake cleaner through it?? Push it down a boat ramp? I can't replace it right now and its a mint pickup, I like it, just want it to run right.