brand new oem denso sensor

brand new oem denso sensor

The only thing I can comment on, then, is that the sensor for the WRX (2.0 turbo) seems to be a different one than that for the 2.5/RS. I don't know which one you're using, or if that's related to your problem. I would suggest trying a Subaru sensor that is meant for the 2003 WRX, since that's the ECU you're using.

 

Other than that, I've run out of ideas. When the wiring gets changed significantly from stock, some of the usual diagnostic techniques aren't valid any longer.

 

It seems to me that the best way to approach this is to either look at the changes that were made, and see if any impact the A/F sensor, or talk to folks who have successfully done the swap and see if they have any further insight.

the sensor is for a wrx, they were way different. Thanks for all the help! i will let you know what the problem was if i ever figure it out, lol

You're welcome. Sorry we couldn't pin down the cause. Please do let us know if/when you get things worked out.

Hey,

 

new info, tonight i checked some other grounds on the ecu and found that pin A7, a15, and c1 were getting a weak ground signal, when i hooked up the grounds to a good body ground, i got rid of the p0031, but in turn i got a p0134 (02 sensor (rich or lean)) the car is running rich (strong fuel fumes in exhaust). This must be some form of progress!

Congrats on the progress.

 

P0134 is "O2 (A/F) Sensor Circuit No Activity Detected". Simply put, it's not being seen by the ECU -- assuming the sensor is good and the correct one, it's apparently not wired correctly to the ECU. It's possibly been that way since the swap, but because the sensor wasn't up to operating temperaure since it's heater wasn't working properly, the ECU couldn't tell. Something to check is continuity of the thin white and black sensor wires back to the ECU.

 

However, be aware that you sometimes can't run ground wires between any two points without consequences. There's a reason why grounds run to particular locations, and usually it's because other paths cause signals to be interfered with. You might want to see if you can trace the A7/A15/C1 ground wiring and find out why it isn't doing the job, rather than adding other wiring.

I made a break through tonight! last week I traced those ground wires and found one was cut, so I got them all re connected but it didn't fix my problem. So, determined that I had figured out all of the wiring, I went out on a limb and bought another front oxygen sensor and VOILA, so more lights! thanks for all the help, esp OB99W. Here are a couple pictures of my project for your viewing pleasure!

Glad to hear you found the problem!

Car looks great!

Are those some kinda huge canons in the background?!

Yeah, that picture was taken at a WW2 military fort that looks over the Halifax harbour in Nova Scotia.