AMUSE

wanna ask any one here know if the O2 censor got problem will it affect the power output from the engine...
which means if the O2 censor got faulty the power output reading from the engine will be hold back from the standard ecu for safty reason??

EZZY

if the O2 sensor fails, the ECU wont get a correct reading, therefore, it will dump as much fuel as possible. take it to mazda and get them to run diagonstic to see if its the O2 sensor.

one of my mates just replaced the O2 sensor on his Honda Accord V6 (i know its a piston engine car, but same principle), the car ran like a dog, was spiting fuels and also backfiring. got a quote from a certain Honda service centre, they quoted him $1200 to supply and fit a new O2 sensor so he told them where to go and we found one else where (used one with warranty) for $150 and fitted ourselves. the O2 sensor on the Accord was accessable from the engine bay, and it was a 5 minute job. :p

e

ps. Honda charged $110 to run the diagonstic :o

Choppy

Amuse did you buy your rx8 second hand?

sco

If the O2 sensor fails it will affect the engine when the PCM wants to run in closed loop. If the engine is in open loop, in theory it shouldn't affect it as the fuel is calculated from a fuel map, rather than looking at the result of the burn.

There are six different faults the PCM can detect with the O2 sensor. The PCM also monitors O2 readings before and after the catalytic convertor to detect a fault in the cat. If there is a fault with the O2 sensor, you should get a check engine light and the car may go into some form of safe mode.

The PCM monitors the emissions system and can report the results of the testing to Mazda's WDS system or a scan tool and this will help the problem get diagnosed.

Edit: P.S. Hymee has a great post on open vs closed loop here: https://www.rx8club.com/showthread.p...osed+open+loop

AMUSE

so thats why my car run slow and rough........
and is it i can buy a new censor from a normal dealer....?
becoz my one i think is already gone......

sco

Are you sure it's the O2 sensor?.. There are many reasons that could cause "slow and rough", such as a problem with the MAF sensor due to a fault or an intake modification. It could be crap fuel. Hymee got misfires and the engine running in safe mode due to crap fule.

Is the check engine light on? If it's on, the dealer will be able to tell you what the cause is.

If you can explain the exact symptoms of the problem, when they occured and what mods you've done, we might be able to give you some idea what the problem is.

takahashi

I think AMUSE car has the O2 sensor touched when he changed the cat.

I don't know mate. It is a complex problem and I won't make a diagnosis until I have the car checked with the WDS.

Deep problem it sounds like

AMUSE

as taka said my car is the O2censor coz i bring bacvk to dealer they check it with the computer and the O2 censor keep on giving the same fault signal to the computer so i
think should be the censor ...

sco

No worries. Get it changed. When you do, It would be great if you could let me know what the part number is. It could be very useful for something I'm working on.

RXP33D

MY GOD!!!
I think I'm panicking now...
I got my car in for 10k service last thursday, installed the K&N intake system that night. I poured a full tank of ultimate that night and it was gone by sunday...
I thought that it was because I was giving it abit too much, but if I recall, it's never been this bad!(drove probably 200kms) What do you guys reckon?

Fuel literally seems to be pouring straight out...And I get a heap of that backfiring noise coming from my stock exhaust compared to usual.

P.S: I'm RX8 illiterate!

takahashi

Check if:

The sensor is on the K&N filter tube.
Engine warning light.
There is a heat shield to the intake - to aviod having a hot air intake

I let 200km/tank at the track, so you may be having too much fun out there

RXP33D

Haha thanks taka! But no way is it possible. Everything seems to be in place, or at least i think it is. No warning light either. But then AMUSE isn't getting the warning light either and losing fuel i think? Maybe have to take it off.

AHH s*^%, the intake was a b'day present from a few of my mates, what are they gonna think of me!!?!?

AMUSE

my warning light is on becoz my O2 censor got problem....

takahashi

Maybe as simple as the contact of the wires, since you have taken off and on so many times

AMUSE

i know ..
thats why i buy a new one today and going to install it tomorrow..

Activematic

Hello, first time i posted on this forum, but AMUSE is it you who has a red rx8 with bodykit? Sometime see around caulfield area.

takahashi

I think that is him. There are not many nutters in Melbourne have loud RX-8s, just kidding dude :D

AMUSE

taka i hate u .....

takahashi

stop being a girl :D

Choppy

ROFL move to ban taka from the forum