My check engine light came on the other day, so i got it checked w/ a friends obdII sensor reader and it came up w/ P0546: Exhaust gas temperature sensor circuit high input.

A lil bit like a week before the light came on the i noticed the car would like hit a wall at around 5500-6000 rpms and start making like a knocking type noise.

We cleared the light and the car ran fine. The light came back on today and the noise came back but around 6500rmps now.

I only have a hks cat back and hks ssqv blow off valve on a 03 wrx w/ bout 14000 on it.

Does any one know why this would be happening?

All help is greatly appreciated, thanks,
tyler.

 

This code usually indicates the EGT probe in the uppipe is bad or disconnected. You don't mention having an uppipe, have you replaced yours and if so what did you do with the probe?
If your uppipe is stock and the probe has just gone bad you should get a new probe, it's necessary with the stock catted pipe to monitor the catalyst temperature. If you have a catless uppipe the probe can be safely removed, the hole plugged, and a 2.2K ohm resistor wired in its place.

 

Hm, thats interesting thanks for the info. I have never replaced the uppipe or gutted teh cat in it. I just kinda find it weird that this would be happening so early on my car.