I got a P0546 error, also known as "Exhaust gas temperature sensor circuit high input". Looks like I'm obviously running lean or is it? Strangely enough tho, this error never veered its head until yesterday under normal load... and I haven't changed anything, no mods, no nothing. It just all of sudden appeared...??? So i'm wondering if the sensor burnt up or something...

Does anybody have experience with this or have some insight on this problem? Please help! maybe the list below might help...

Current engine mods and setup:
HKS down and up both have no cats. (CEL but fixed with resistor)
GReddy EVO cat-back. (I got no cat so is it still a cat-back? haha)
GReddy MBC set at 1.2 BAR or 17 psi. (been running it, no prob)
Foam drop-in filter. (no CEL)

Isn't that the code the stock EGT sensor would throw with high EGTs.. is your resistor fix you said you have for the upipe sensor, or the 02 sensor in the rear exhuast for the P0420 code?

Do you still have the stock EGT sensor in the HKS upipe? Or is the resistor fix there? If you have stock egt sensor in there, and a MBC I'm guessing that high EGTs at part throttle is triggering the code..

I'm trying to find out if the second O2 sensor on the downpipe is one, also a EGT sensor and two, if not then can it also trigger the P0546 error??? As far as I know, the only error that the second O2 sensor sets off is the P0420 error, also known as "Catalyst system efficiency below threshold" usually due to a blown cat or a no cat. :D

Originally posted by PaulRex
Isn't that the code the stock EGT sensor would throw with high EGTs.. is your resistor fix you said you have for the upipe sensor, or the 02 sensor in the rear exhuast for the P0420 code?

Do you still have the stock EGT sensor in the HKS upipe? Or is the resistor fix there? If you have stock egt sensor in there, and a MBC I'm guessing that high EGTs at part throttle is triggering the code..

Just found out that the second O2 sensor will NOT set off the P0546 error. The part 22629AA012, otherwise known as "Sensor assem. ex. Temp" is solely responsible for this error. Also found out that once detection's been made, the sensor is most likely cooked thus requiring a new assembly. Luckly the new part isn't too expensive and easy to install but my problem still persists: Engine running too lean; EGT above threshold...

Does anyone know what idle and full load fuel pressure should I be running if I'm runnig 17~17.5 psi? I have intake, downpipe, uppipe and cat-back exhaust.

p.s. please help a.s.a.p. I am running lean, quite lean... (sensor burnt off) :D

p.s.II what is the safe range of EGT on WRXs?

Turn down da boost.

Originally posted by Brahmzy
Turn down da boost.

I second that, especially without engine mgm't to tune the fuel map etc.

Its probably time to up the fuel pump, and go for some larger injectors, with a computer tune. That way, you can really enjoy the extra boost.

Later,

jcnel.

You will norrmally get that code when you run 5 th gear 80 mph
for more that 5 to 10 seconds. The ETG probe goes flat line. That is what throws the code.

If you stay out of the 5 th gear 80 (changing speed ) for more that 5/ 10 second you will avoid the code. It will clear after 5 runs.

The main concern is that the probe can get toasted and flake off into the turbo. The fix is to move it to the down pipe.

I have ran for 60,000 and I'm still ok in reguards to the EGT.

Me being Mr. Dumass I floated my valves. :furious: :mad:

I have to put miles on my STI now :banana:

WRxzard

Originally posted by WRXzard

I have ran for 60,000 and I'm still ok in reguards to the EGT.

Me being Mr. Dumass I floated my valves. :furious: :mad:




How? Care to elaborate?

I just checked and I am getting this same code. All I have is Vishnu Up-pipe, Stromung Downpipe (w/high flow cat), Stromung 3rd cat eliminator pipe, and Cobb Catback. The CEL does go off after a while but just comes back on shortly.

*edit- I also have the "resistor CEL fix"

The P0546 code usually means that your up-pipe O2 sensor is ready to die. If it dies your car will only run in limp mode (not fun).

This has nothing to do with high egt.... it actually means the sensor is seeing a lower egt than it is supposed to. I would pull the plug on the sensor and place a 2.2kohm resistor in it's place. Remove the probe from the uppipe and replace it with an M12x1.25 bolt.

There's been a ton of posts on this very thing. A simple search will lead to you hundreds of similar posts.

Good luck.

Edit: As a side note though, you really should turn down that boost. 17 psi is definately on the borderline of pushing the stock turbo out of its efficiency range. You'd be much safer running 15-15.5 psi, unless you are looking for an excuse to blow your engine up.... ;)

17 is a very bad thing on stock sytem/turbo with no management.