Bad maf?

So the dealer finally looked at my car, their response was "we aren't allowed to work on modified engines, but all tests point to a bad mass air flow sensor"

My only mod is a catless up-pipe and resonator delete

Haha, I never heard of that before especially with every wrx and sti I can't believe they say that

Anyway, does a bad maf seem like it would be the cause of my car having no power when I am trying to pass someone on the highway?

feel like its breaking up and spitting and sputtering? sounds close to the issue i had

reusable air filter/oiled air filter in it?

Have you cleaned the MAF sensor ? Get a can of MAF cleaner from the auto parts store.

Remove the two screw that hold it in, pull it out, spray upthe tube a little and around the IAT probe let it dry, put it back in.

If you get a CEL, just pull the negative battery cable for about 15 min's then put it back on, turn the key to run, for 30 seconds then turn the key to start, then take it for a drive.

Oh Yea, don't let the dealer touch your 2005. Find a good local repair shop and stick with them. I have been using the same mechanic since the mid 1980's, I have a close network of machine shop, body shop, tranny guy and repair shop, they all work together if needed.

Ask and look around your area, you can find that too.