Hello.

 

I have recently thrown a couple codes in a stock '02 WRX 2.0l MT and am hoping somebody has seen them before. The first was a 'C0300' which I think is listed as a "Rear Speed Sensor Malfunction" but could be wrong. I've never thrown a chassis code before and after asking the local Stealership about it they have never heard of this code.

 

The second code was a 'P0400' which I believe is a "Exhaust Gas Recirculation Flow Malfunction". This code has occured twice and occurred after starting the car and driving it a short distance (less than 1km) at very low speed (30km/h) and it threw the CEL when I got off the throttle for a stop sign.

 

I've scoured the net and various board's trying to find someone else who has seen either of these issues on a WRX with no luck. If anyone could point me in the right direction for either or both of these codes it would be appreciated!

 

Derrick

 

Do you get a steady CEL being displayed, or does the check engine light come on, and then turn off?

 

I typically recommend you clear the codes and see if they come back. That way you determine whether the issue is a fluke or not.

 

I'd also recommend checking out http://forums.nasioc.com/forums as there's a TON more WRX owners over there that could have experienced similar codes.

It was a steady CEL in both cases. I've cleared the codes twice now and they re-occured within a couple days so any day now they should reappear. Thanks for the response.

 

Derrick

 

 

Do you get a steady CEL being displayed, or does the check engine light come on, and then turn off?

 

I typically recommend you clear the codes and see if they come back. That way you determine whether the issue is a fluke or not.

 

I'd also recommend checking out http://forums.nasioc.com/forums as there's a TON more WRX owners over there that could have experienced similar codes.

Hmm.....The fact that the codes don't come back immediately would have me lean towards the fact that the sensors themself are probably ok, but that something else is causing the issue.

 

Have you been able to correlate driving conditions, location, or anything like that back to when the codes occur? Do both codes reoccur, or just one?

 

Are you experiencing any other driving issues?

 

My far fetch guess would probably be that there's an electrical wiring issue somewhere, that comes & goes.....

Hmm.....The fact that the codes don't come back immediately would have me lean towards the fact that the sensors themself are probably ok, but that something else is causing the issue.

 

Have you been able to correlate driving conditions, location, or anything like that back to when the codes occur? Do both codes reoccur, or just one?

 

Are you experiencing any other driving issues?

 

My far fetch guess would probably be that there's an electrical wiring issue somewhere, that comes & goes.....

 

I've also posted these codes to the nasioc board and there is some debate as to whether the codes I read were correct as they don't make sense to anyone. I'm going to wait until I throw a CEL again and then read it with a different piece of software which hopefully will shed some light on the problem. I'll report back when I know more! Thanks.

 

Derrick

Sounds good.

*as posted on nasioc*

 

Finally threw another CEL today and it turned out to be a P0304 (cylinder #4 misfire). Turns out that my software is broken due to a simple parsing error. Sheesh.

 

Last time I threw a P0304 it was a bad plug (stock Champions) so I replaced them with NGK 6962's and it hasn't thrown it again until this week. Only have 15k km on those plugs...hmmm. I have a new set of 6962's that I'll put in but I'm a little surprised to see this code rear it's head again.

 

Derrick

I am also getting the Exhaust Gas Recirculation Flow Malfunction error on my 98 Legacy GT. I have cleared it several times. It seems to come back after 2-3 weeks. I think it may be related to the hole I developed in my exhaust. I expect there may not be enough back pressure.

 

Have you check the EGR solenoid? It is located on the back of the intake runner closest to the driver on mine. I think it is similar on the WRX. It is vacuum solenoid the moves the plunger up and down. You should be able to push it with your fingers. It will have some resistance, but should be smooth. Make sure it moves all the way it and doesn't bind or drag. If it is sticking it could be causing the code.

 

I started getting misfire codes when my knock sensor went. Are you getting anything other then that one?

 

Rob

I am also getting the Exhaust Gas Recirculation Flow Malfunction error on my 98 Legacy GT. I have cleared it several times. It seems to come back after 2-3 weeks. I think it may be related to the hole I developed in my exhaust. I expect there may not be enough back pressure.

 

Have you check the EGR solenoid? It is located on the back of the intake runner closest to the driver on mine. I think it is similar on the WRX. It is vacuum solenoid the moves the plunger up and down. You should be able to push it with your fingers. It will have some resistance, but should be smooth. Make sure it moves all the way it and doesn't bind or drag. If it is sticking it could be causing the code.

 

I started getting misfire codes when my knock sensor went. Are you getting anything other then that one?

 

Rob

Hi Rob.

 

I recently learned the WRX doesn't have an EGR solenoid so there's nothing I can check there. As for the knock sensor I haven't thrown any other codes than that P0304. My initial two P0400 and C0300 codes were incorrectly reported due to a software bug and there really was only the one P0304 code. However, thanks for the heads-up on the knock sensor and it's relation to these misfires.

 

Derrick

I am also getting the Exhaust Gas Recirculation Flow Malfunction error on my 98 Legacy GT. I have cleared it several times. It seems to come back after 2-3 weeks. I think it may be related to the hole I developed in my exhaust. I expect there may not be enough back pressure.

 

Have you check the EGR solenoid? It is located on the back of the intake runner closest to the driver on mine. I think it is similar on the WRX. It is vacuum solenoid the moves the plunger up and down. You should be able to push it with your fingers. It will have some resistance, but should be smooth. Make sure it moves all the way it and doesn't bind or drag. If it is sticking it could be causing the code.

 

I started getting misfire codes when my knock sensor went. Are you getting anything other then that one?

 

Rob

 

Hi Rob.

 

I recently learned the WRX doesn't have an EGR solenoid so there's nothing I can check there. As for the knock sensor I haven't thrown any other codes than that P0304. My initial two P0400 and C0300 codes were incorrectly reported due to a software bug and there really was only the one P0304 code. However, thanks for the heads-up on the knock sensor and it's relation to these misfires.

 

Derrick

My bad...

 

I usually just oogle the turbo and the intercooler under the wrx hood, so I haven't noticed much else.

 

My hood scoop is for cooling the brake booster:grin:

 

Thanks for the info.