January of 2013 I had a small fender bender in my evo 8 that knocked the intercooler off the mount and bent the piping so when it went to the body shop they sent it to a performance shop (full blown motorsports in mn) to put the intercooler in and fabricate the piping. After I got it back it was running rich (p0172) and had a high idle (p0507 I believe) and also was not boosting consistently (boost would never go above 8 and car would jolt forward and back while accelerating).
Brought it to a different performance shop (db performance in rogers mn) that was recommended by a buddy of mine with an evo 8, they did some diagnostics and ruled out a bad MAF, bad ECU, and a couple other things I can't remember. They said they tightened a BOV hose clamp and it seemed to not have the inconsistency as much but still wasn't boosting.
From there I brought it to a mitsubishi dealership, they found a bad o2 sensor ( don't remember which one, I will update after checking the invoice) which they said helped the fuel trims a little but it still ran rich.
At home I unclamped a BOV hose that ran from the intercooler piping to the BOV and reclamped it tighter and was using brake clean to see if there was an intake leak which was my original theory but came up empty.
I brought it back to the original performance shop (full blown) and they retuned it and replaced the boost controller. Their theory was that it had a bunch of aftermarket upgrades to it but when the previous owner sold it they put the original parts back in without tuning it. It boosts now but still runs rich and at high rpms has a little inconsistency. Scan data at idle shows it going back and forth between rich and lean. my mechanic thought that the voltage on the MAP sensor seemed low but havent had time to test it since.

Does anyone have any ideas?

 

What is your definition of rich? I assume this is on 93..?

 

It's like jogging but at a slightly faster pace and you have bags of money in your hands?
Lol jk but seriously, burning too much gas. What other definitions are there?
It's an 05 evo 8

 

What is the air fuel ratio?

 

It sucks no one has been able to solve your problem. You may have to take it upon yourself and do a little more research. I mean that in a helpful way.
Do you have an AFR meter? Like AEM or Zeitronix.
Also, what plugs / gap are you using?

It does sound like you are running a fuel map that has been tuned for fuel demanding mods. However, we have no idea what your car has, mods, or mileage.
Could also just be a bad FPR.