OK, this might be better in another place, but I'll start here.

The TB seals on my IX were leaking pretty good. So I got the Mil-Spec seals with the new TB gasket and did the replacement. I very carefully marked the TPS sensor against the throttle body during disassembly.

The car has 50k on it and the butterfly plate, shaft and engine side of the TB had some serious sticky carbon build up. So using some carb cleaner on a rag I cleaned everything up nicely before installing the Mil-SPec seals and re-assembling.

Using Evoscan, my TPS feedback at idle before the swap was 13.1. Afterwords it is now 12.9. I figured that is damn close

Car runs great, but now it idles at 1100 rpm's. Checked the throttle cable and yes the butterfly is going all the way closed against the stop. Is that 0.2 difference in the TPS reading at idle causing this? Since it is actually -0.2 wouldn't it idle lower?

What am I missing here?

 

Could have gummed up your IAC when you cleaned the TB. I'd check that out. And as always, check for the pesky vaccum leaks.The difference in TPS feedback could be due to the removal of the carbon buildup, I guess?
Hope this helps

 

Did you clean EVERYTHING off the inside of the TB? Mitsubishi puts a small coating in there that if removed can mess with the idle. I believe they use molykote 321. Search on here for some more info.

 

This sounds right!