So why would I get a P0546 (high EGT)?
I have a feeling but tell me if I'm right. Mods are: gutted OE uppipe, catless turbo-back, Samco I/C hoses, and STi hoodscoop.
OK here's my theory. When I put the STi scoop on I didn't reset the ECU. It was a cool night and I was cruising on the freeway in 5th I started going up a pretty steep grade but left it in 5th. Under a high load/boost situation, the ECU didn't compensate for the extra cool charge air and I ran lean.
I didn't think the STi scoop would make a difference. Am I on target here?