Well you have gone and replaced things that most would have suspected to cause the issue.

Considering that this mainly happens when outside temps are approaching 90 or above. Next I would probably flush the radiator....maybe even replace it. (presuming this is a Automatic trans) The reason I mention replacement is the radiator has a built in trans cooler in it.
Depending on the style of internal cooler it can be real difficult to flush that internal tranny cooler out. The internal cooler for transmission can get restricted and cause the trans temps to run towards to upper limit.

Have you even taken the upper intake ( the 90deg bend down toward the engine), or as know as, the throttle body housing off and cleaned the internal area. They can get build up of crud and carbon deposits and plug or heavily restrict a couple of EGR ports which can cause runability issues.
How old are the spark plugs? and the boots?
Have you checked for vacuum leaks??

 

Hi,

Thank you, Enriched&Beyound, this is helpful.

It is an automatic transmission. I will flush or replace the radiator when I get some free time. It does not overheat, though.

I did take off the upper intake/throttle body housing, actually this weekend. I was trying to clean/replace the IAC valve, because I was reading that this could cause my issue. I rounded off the bolts on the IAC valve and had to take the upper intake off to hammer an extractor on and get the bolts off! Anyway, I cleaned all the crud off the intake and ports.

The plugs are probably pretty old. I doubt they have ever been replaced. I have replaced all of the boots with the coil packs over the last several years. When a coil pack was bad, it would misfire and throw a code, but that was always superimposed on this other issue.

I will have to look up how to check for vacuum leaks.

Thank you for all of the help. I will keep working on it, and see if it still happens.

 

I know you said your not too experienced but it's time to do some diagnostics for something to point to the problems or keep guessing and hoping to get a fix.
First, the 1000 code is not a trouble code. It tells you all system diagnostics are not complete.
If your going to service your self you need to look at live and stored data.
When the problem occurs, you need to be ready to look at some items while the problem is present.
For example fuel pressure, measure it with a pressure gauge.
Use scanner to look at the record of cylinder misfirers possibly indicating a faulty coil.
Until you come to this point, your issues will just continue.
I makes no difference what was replaced in the past, it what's wrong now that counts.
Good luck.

 

Did you round off the IAC bolts using standard sockets on a metric bolt? You say the spark plugs probably haven't been changed. That may be a good place to start by removing one and checking condition and gap.

 

This is great! Thank you for all of this advice!!

As for how the IAC bolts got rounded and whether or not an SAE wrench was involved, I would rather not say because I don't want to lose any credibility or confidence here! I listed all of the stuff I had replaced just to make the point that this issue has been going on the whole time and replacing that stuff didn't really help.

Personally, I am hoping that cleaning the intake and replacing the IAC fixed the problem! If not, it looks like I have a to do list starting to form.

1. Check a plug/change them (I've been itching to do this for a while).
-Replace with Motorcraft plugs, 0.054 thousandths of an inch, right? I know I need to do this while the truck is cold and pull the coil packs off and spray some penetrating oil or something on them the night before, right? Any other advice/links?

2. Check the fuel pressure (I need to get the stuff and learn how then be ready the next time the truck is having the issue).
-Any links or advice would be helpful!

3. Check the vacuum for leaks (Probably relatively simple, but I need to look up how then be ready the next time the truck is having the issue).
-Links, advice?

4. Scan with an OBD scanner for history and while the truck is having the issue.

5. Flush the radiator or replace (not really excited about replacing another part for ~$150, might do this last especially since it isn't leaking or overheating).
-Comments about this or how important this is to my problem?

 

We have a 2001 f-250 XL for the farm that did the same thing when idling or long drives in the summer, we never ran it into the red though so I have no experience with the stalling. All we did to fix it was thoroughly wash and blow out the rad. Or if the your fins are all messed up you can buy little plastic tools to straighten out the fins to the correct spacing.

 

Theres a chance your catalytic converters may be pluged up or your muffler migh be nicked causing a flow ristriction, an easy way to check for clogged kittys is to remove the upper O2 sensors on both banks and drive it iy you feel it has more power and the truck doent stall you found your problem. Just a side note its going to be freaking loud and you will end up with O2 sensor codes.

 

 

A code reader is not what you want. It only reads codes set.
A Scanner is in order so you can look at operating data due to how the problem comes on.
A loss of power as described is a loss of fuel, overheating etc if the motor continued to run.
It's the only way to get a lead on the cause.

 

 

It would have been cheaper to look at the cause when it happens.