I'm certain.
It took me an impact driver to get mine out the first time. After that, it was a piece of cake
Look at the picture I posted above. You can see the cover off and slightly away from the hole and having arrows pointing to it, and the hole it covers. I believe it's threaded because the idle adjust screw has to screw all the way down from the entrance, and a threaded cover is more secure than just a cheap plastic or rubber cover. If you hadn't noticed how really secure it is It will keep air, dust, water, etc etc out. The passage the idle adjust screw closes or opens isn't very big, so it doesn't take much to clog it up, and there goes the idle completely.
Don't forget, these trucks are designed for off-road, and that be a pretty harsh environment. I don't go off-road any more, but I did when I was in Yuma, and the desert is HARD on vehicles! Easy on the body, hard on the mechanical parts, like the engine, just for example

I actually did think the cover screw was the idle adjust screw myself, and tried to tighten it, and loosen it, to adjust the idle. Once I got it off, and actually found the idle adjust screw proper, it suddenly worked like a champ. I could adjust the idle through a fairly broad range, with very small adjustments.
I'm just glad I have an impact driver in my tool box, or I'd have been stuck completely.
Maybe just a whack or two with a ballpeen will loosen it enough to get it going. Not hard enough to damage it, obviously, but just to loosen it.
If it comes down to it, you may have to drill it. And replace it, of course. MAY have to drill it.

See if you can borrow an impact driver off a friend, or auto parts store. A lot of them have a "borrow a tool" set up. Heck, they might even come out to the parking lot and break it loose for you. That way, you can blame them when they strip out the head of it

Good luck, and let us know how things go! If your IACV is in fact bad or having problems, you may well need to adjust the idle once you replace it. You may need to adjust it for a LOT of reasons. A lot of parts that go bad and need replacement can change the idle, and then where are you? Better to get it squared away now than when you have other problems you need to work on.
Heck, even setting the timing requires the correct idle speed to do correctly, and you might need to do that after you replace the distributor cap and rotor, for example. I do that every spring, among several other parts, and set the timing afterward. I want my trucks to last me another 30 plus years! A little preventative maintenance NOW can save a LOT of heartache later, you know?

Good luck!
Pat☺

 

Well, I'll have to investigate this idle cover later. I "burped" the cooling system. There were a few medium sized bubbles that came out. Still didn't change anything with the surging idle. So I guess it's down to the IACV.

If I'm going to get in there and take that whole assembly off, I'm replacing the IACV. I'd hate to attempt to clean it, put it all back together and still have an issue. I may still have an issue after replacing the IACV, but at least I'll know it's not that part.

It would seem Rock Auto has the best price for that part. Thanks for the tip...would've paid 125 for it otherwise.

 

RockAuto has 5% off codes, so just Google it to find a code.

Those screws on the IACV are a PITA. I could not break them loose with a screwdriver. I had to use my impact wrench with an impact screwdriver. They spun right off easily using the impact. My IACV did come with a new gasket. You don't need any sealer with the gasket. Just snug the screws down.

 

I already ordered it. Thanks anyway. I'll have to go see if harbor freight has one of those..pretty sure I've seen em there.

 

I gotta hand it to Rock Auto for their shipping speed. The IACV is already out for delivery..I had to check the tracking twice because I didn't believe it.

I also got one of those manual impact drivers for $8 at harbor freight.

 

Well..dove into work on the toy today. All in all..so far so good. Like an idiot I tried to get the one of the screws to the IACV off with an impact wrench. Of course I stripped the head, so I took the others off with the manual impact. Took some beating but they came off. Had to drill the head off the stripped screw. These look pretty standard. Off to Home Depot.

I also managed to crack the plastic (really?) Intake air hose (that connects to the throttle body. Luckily it cracked near the edge. Wrapped some electrical tape around it until the new one arrives. It's basically cracked parallel with the clamp so the tape should hold so long as I can get it back on without further damage.

 

Well, I am pleased to report that the surgery was a success, and the idle surge is gone. Was a little worried about stripping the intake manifold..seems like it's made of aluminum. Had to be careful not to over tighten my bolts. All seems good..no leaks.

Hopefully she'll pass smog now.

 

It's fixed yay!

Looks like the IACV was partially clogged.

 

That may have been the initial cause, maybe not. But at least I have a nice shiny new one on there now so it's all good.