IAC really badly crudded up - bigger issues?

Truck threw a TPS code today so I pulled the throttle body to clean. Was real dirty but nothing too weird except there was some fresh, clean oil in the intake when I stuck my finger in. Bad PCV maybe? Then I opened the IAC to clean it and this is what I found!

Not great. Those are coolant passages, right? I'm guessing this means I should be worried about what state the head and block passages are in? The truck has 220k, I've only had it for a few months. When I bought it I drained the coolant and replaced, it had green in there so I went with green. A proper coolant flush and replacement with yota fluid is on my list I just haven't had time, now I'm wondering if I've got bigger issues than just a basic flush and refill will solve. Thoughts?

 

With 220 it could be the start of somthing like a head gasket but you also don't know the intervals of the last coolant services or what quality it was. I would good a proper flush with toyota or good quality fluid and reinspect in 6 months depending on how much your drive and see how it looks then.

 

Makes sense. I'll start there.

 

Is that rust or the residue of some sort of stop leak ??

Then you never know how well things were cared before.

Seller drained old rusty coolant filled with new you never know