jtanner

Hi everyone,

Long story short, driving home at 1am up the motorway about 85mph... car in front (plenty of gap between) must have hit an animal... I have zero chance to avoid the road kill, and thusly bump over it too

Now I have the CEL on and error P0037. I'm guessing the accident with whatever it was in road has damaged my rear o2 sensor based on the obd code. Is this possible?

I saw another thread that said you couldn't damage the sensor without ripping the cat off? So perhaps it's just the wiring?

I'm new to RX8's but pretty good with cars in general (previously owned a very fast impreza sti) so could some one point me in the right direction of what to look for, where to check etc.

I'd like to jack it up myself and take nosey myself before shelling out money to fix. Can anyone post a guide or pics of what to look for? Or perhaps any other advice?

Also, can someone tell me the risks / dangers of running this faulty rear sensor?

Many thanks in advance.

RIWWP

iTrader: (2)

Yes, you almost certainly had the wring to the O2 sensor ripped/torn/damaged, etc... Voltage too low is usually a complete severing of the respective wire in the harness, voltage too high is usually an internal sensor failure.

If you get on the ground next to the driver's door and look toward the middle of the car, the O2 sensor in question is visible sticking out from the cat, with a bit of a flimsy shield around it.Shield may be missing, damaged, etc... if you had damage in that spot. Jacking up the driver's side will give you plenty of room to work with, pretty easy to change yourself.

jtanner

Thankyou RIWWP, I will take a look. Is it definitely Driver Side? I saw on another thread here that it was on the Passenger side?

Mine is a 2004 UK (RHD) Model. I'm hoping it is repairable but I guess that depends on the extent of the damage.

What is the rear sensor for? In otherwords, what does it affect by being damaged / out of action.

I have a PLX2Wifi gadget, and it tells me there are 4 problems reading readiness monitors (All related to that sensor I believe) and of course the stored code is

"P0037 - H02S Heater Control Circuit Low Bank 1 Sensor 2"

RIWWP

iTrader: (2)

Ah, sorry, US LHD's driver side. So yes, your passenger side. Without any location info I made the assumption that you were in the US.

The rear sensor is used for emissions control and it refines fuel trims during stable cruising, as the narrow band O2 sensor reports more accurately and faster than the front wideband. It is not critical to the operation of the car.

Yeah, you probably have that wiring harness sheered through then. Probably have heater voltage too low, not reading the sensor, sensor voltage too low, sensor voltage not changing, etc... Most of them require a drive cycle or two in order to store the code. Also possible that the plug was just yanked out and you might need to just plug it back in. IF the damage is between the sensor and the plug, a new sensor is the best bet, unless you are great with wiring it back together. If it's downstream of the plug in the main harness, you will need some wiring skills or someone that can do the wiring for you. Or a complete engine harness, which is REALLY overkill.

jtanner

Thanks RIWWP, It was a sheer snap ... now to try and find a second hand on OR a very cheap one... not long started renting so I'm brassic atm (always happens at the worst time)

To help anyone else who read this with similar issue... I've attached pics of the damage!

Does anyone happen to know the part number that I will need? Prices (new) seem to range from Ł100 - Ł450 :-/ all seem to be the same part

j9fd3s

Mazda part number is N3H1-18-861B for the 5 speed and N3H3-18-861B for the 6 speed

jtanner

Thanks j9fd3s