I can start from home about 1 mile down the road the truck runs terrible, and loses almost all power, and speed. It almost stops. If I keep my foot in it, it still doesn't have power, and backfires. let it sit for a short time it runs good like nothing happened. Then for no reason, the problem I just described returns. It had one code No 3 miss fire. It did have one cylinder not firing, when this all started. The code is gone, and the engine runs good when it runs. Any suggestions? Stan

 

The good news is the 4.2L is a pushrod engine which automatically rules out most of the problems with Ford engines. As a guess, I'd say its running out of fuel. I would look at the fuel pump driver module which is on top of the rear frame cross-member. If the bottom of it looks corroded that might be your problem. Then there's the fuel filter. it could possibly be the fuel pump. Another poster had a somewhat similar situation with a V8 and it looks like its the plugs and coils.
Just curious, did this start suddenly? I'm wondering if you got some bad gas. Or, has the truck been sitting a lot without a stabilizer in the fuel?

 

Intake manifold runner control


found one for F150

 

Sounds like the MAF sensor to me.

 

A lot of people don't think it's a good idea to just throw parts at a car. I'm different. I think you should throw parts. Start with maintenance. Do everything that should have already been done. You are driving an '05. It's 2019. Change the fuel filter. Rotate the tires. Change the rear differential gear oil. Run something to clean the injectors like Lucas or Techron. Change the spark plugs, wires, and ignition coil. Clean the MAF sensor. Change the air filter. Flush your transmission. Change your oil. Get a new stereo. Hang some fuzzy dice. Do everything you can think of, then do whatever you did not think of, that other people are telling you to do.

While everyone has a piece of good advice; nobody on the internet is actually looking under your hood. Reality is that you should have someone more qualified than yourself, take a look at it. Bring it inot a shop for a quote. See what a dealership tech says.

 

You forgot curb feelers!
He is correct though. Take it to a Ford dealership and have it checked. It sure will save A LOT of money just throwing parts at it.
(Do install the curb feels though!)

 

Dealership techs only work on Ford, and in some cases, only certain parts of the car. They are trained, and their training is updated, by Ford. They have access to the Technical Service Bulletins, recall fixes, and have proprietary computers for diagnostics on your Ford. So let's say that there is a tech who is the transmission guy, he only services Ford transmissions. He didn't just perform a tune-up on a 97 Toyota Camry, change suspension on a 14 Fiat, change oil on a 03 Range Rover, and now he is going to check your engine's compression. It's like going to a fancy restaurant, where a whole crew is in the kitchen, and they are all trained to do one thing with expert precision. The pastry chef isn't making fries, and the cold station guy who makes salads isn't grilling your steak.

Dealerships are expensive. Sometimes the hourly rates for labor are double compared to an independent shop, and the parts are always marked up to full MSRP.

In some areas, you can find independent shops that specialize in your vehicle. There's a guy who puts videos on youtube.com , FordTechMakULoco , who is an example of a shop which works on Ford. In my area, there is Mostly Mustangs, which specializes in Mustangs. I live in a major metropolitan area, so those kinds of shops are easier to find. Sometimes a good starting point is your local speed shop. The parts counter guy will probably know of a good mechanic whom they distribute to, and based on what he orders, knows that this shop works on a lot of Fords.

 

On my truck, with a 6" lift, those curb feelers are high enough to tickle your "your know what".

Most of the time, based on personal experience, there is a lot of deferred maintenance on 10+ year old cars. Doing some of the maintenance isn't such a bad idea. He probably does need new gear oil, new transmission fluid, new shocks, new fan belt, new hoses, et cetera. You don't want to be the guy who has a ring & pinion failure, only to find out that if you only changed the oil........