Loud clunking and bouncy idle upon start...then goes away

Alright, so I've got another one for you guys. Just today my car has decided that upon starting up (which is immediate and powerful, no problems there) it will have a sort of unstable idle ranging from 700-1100rpms and a reasonably loud clunking coming from the engine compartment. Not sure where more specifically yet. Anyway the rest sounds fine and the clunking goes away in under a minute or less every time

The more I listen (have to wait like 30mins between startups to hear it) I think it may be an issue of needing new plugs? It's way overdue for a change (98,711miles). Like its keeping all the cylinders from firing or something along those lines? I'm not the most mechanically inclined but this is my stab in the dark, sound at all realistic?

One more post!!!

So my old man came home (oldschool car guy, very knowledgeable) and he listened. First thing, he agrees it desperately needs new plugs. But he heard less of a clunking and more of a grindy bursts of squeak coming from the idler pulley....suggests new pulley and some injector cleaner to fix up that surging idle. But then I realised, my Ac compressor is leaking (internally, that's why my ac keeps draining out) and the idler pulley is on the same belt as the compressor! And this issue never appeared until my leak became more frequent....related?

Plugs, if you haven't done them before, yes.

Wires, too.

Your dad could be right about the idler pulley. They aren't that much. Buy one and swap it on. If it's not the problem, return it or keep as a spare. I think I have 2 or 3.

If the AC idler is your issue, you should be able to replace it without removing the compressor. But in your case might make sense to replace the entire compressor if you system isnt performing up to par.

To identify where noises are coming from, I recommend a mechanic's stethoscope. There's a good one at Amazon for $20.

I suppose a stethascope would be a tad more developed than his method of placing a screwdriver to the different components with his ear on the other end, works though haha

But yeah, I'll probably be looking at just replacing the whole compressor since I need to anyway. My local guy quoted me at $850 after parts and labor (since its a weird three part unit, the radial 6 or whatever they call it) My dad was wonderin how hard it'd be to just make the swap himself. Anyone here done it at home?

I had just begun to notice, there's sure been a hefty number of unrelated repairs I've had to put into this car since buying it a month ago. BUT, I also just considered she hasn't been drivin heavily over the past 18 years and is finally just getting on up closer to that wonderful 100k parts swap age so really, I'm hopin most things will taper off for awhile after getting tended to

I just picked up a use compressor from a yard for $75. It's not that hard to replace. Here's a write-up:

https://rivperformance.editboard.com/t6120p45-write-up-ac-compressor-clutch-replacement#131806

Actually, most parts should not be failing at 100k, except for suspension, brakes, and other regular maintenance items. 150k seems to be the age I noticed things starting to fail, like the transmission for example, and some other more costly repairs. Still, they aren't that bad, and once you fix them, you should get another 150k at least.

Another detailed writeup! Woot! I love how many there are here!
We'll scour the local graveyards for some parts and give it a whirl on our own then. Today while driving it, I noticed that whenever idling it gets pretty grumbly. Anytime I get the rpms up above 1k it purrs like a kitten. Very weird. Hoping its the idler