O2 Sensor

ThilakR · January 9, 2008

Hi Gurus

My car suddenly indicate Check Engine light and subsequently found the O2 sensor is malfunctining.

Finally costs me 21k for the replacement at A*W. Some ppl say this is due to the quality of fuel we use. 95 Oct.

Is this correct? Or is there any other reason which I missed by any chance?

Thilak

Nilantha · January 9, 2008

ThilakR said:
Hi Gurus
My car suddenly indicate Check Engine light and subsequently found the O2 sensor is malfunctining.

Finally costs me 21k for the replacement at A*W. Some ppl say this is due to the quality of fuel we use. 95 Oct.

Is this correct? Or is there any other reason which I missed by any chance?

Thilak

whats your car model? FB15?

Arc Angel · January 9, 2008

since you took it to A*W i'm assuming this is the sunny with the inherent o2 sensor issue. not sure if our fuel has anything to do with it, but i'm no expert...

The Don · January 9, 2008

ThilakR said:
Hi Gurus
My car suddenly indicate Check Engine light and subsequently found the O2 sensor is malfunctining.

Finally costs me 21k for the replacement at A*W. Some ppl say this is due to the quality of fuel we use. 95 Oct.

Is this correct? Or is there any other reason which I missed by any chance?

Thilak

The quality of fuel does have an effect of O2 sensor malfunction, as high levels of sulfur cause the metals inside the sensor to corrode faster, which is the case with our fuel in SL.

Part of the problem is our import of domestic models vehicles built for the Japaneses market, as fuel you get in Japan is one of the cleanest in the world with very low levels of Sulfur

But the problems with early model Nissan's is probably a manufacturing defect as they fail much earlier than other cars.

xXx · January 9, 2008

The Don said:
The quality of fuel does have an effect of O2 sensor malfunction, as high levels of sulfur cause the metals inside the sensor to corrode faster, which is the case with our fuel in SL.
Part of the problem is our import of domestic models vehicles built for the Japaneses market, as fuel you get in Japan is one of the cleanest in the world with very low levels of Sulfur

But the problems with early model Nissan's is probably a manufacturing defect as they fail much earlier than other cars.

Yes as Don pointed out poor quality of fuel is the root to his issue.

Don, wasn't it the air flow sensor that previous model Nisans struggled with

The Don · January 9, 2008

xXx said:
Yes as Don pointed out poor quality of fuel is the root to his issue.
Don, wasn't it the air flow sensor that previous model Nisans struggled with

Might have been, but the FB15 (and even the march of that generation) certainly struggled with the Oxygen sensor on the exhaust manifold.

Another common problem is the cam sensor

The really silly thing about it was that some of these sensor failures caused the Nissans to stop dead but this problem was rectified in later models.

Ripper · January 9, 2008

The Don said:
The really silly thing about it was that some of these sensor failures caused the Nissans to stop dead but this problem was rectified in later models.

shiites that sucks... i thought the ECU automatically goes to default settings and gets the job done without the o2 sense providing real time feedback!

The Don · January 9, 2008

Ripper said:
shiites that sucks... i thought the ECU automatically goes to default settings and gets the job done without the o2 sense providing real time feedback!

Yes even I could not understand why they could not just flash the check engine light and go to default settings and carry on. I think if the after cat oxygen sensor was the one to fail, the catalytic converter failure sign will come up but the car will not stall.

I am quite ashamed to admit this but the catalytic converter failure sign has been on my mirage since the day it was brought due to the failure of the oxygen sensor, but not a single mechanic including Wasantha has taken any interest in replacing it, which is quite frustrating, they all keep passing the ball and making suggestions, and I might have to do the unthinkable, take the car to UM.

maithri · January 9, 2008

Guys,

O2 sensors fail for many reasons but the warning light comes on mainly when the heater in the sensor is faulty. This is easy to monitor for the ecu so as soon as no resistance is felt it puts the light on but if the car is running ok be careful not to ignore it as the car will start to overfuel and cause premature failure of the cat and lead to excessive wear to the cylinder bores. How ever a cat is not needed in Sri Lanka to stay within the law-so as long as you have no second checking o2 sensor fitted after the cat it is not worth spending money on unless you want to be eco friendly.

The cat does not perform any other function other than cleaning up the gasses emitted by the engine by converting co into co2.

95 octane fuel is common in the west and the O2 sensors generally last around 60,000 miles in good working order. If you test the signal output using a scope you will see the function starting to become erratic much earlier. So I would not blame the fuel unless you see a lot of different models suffering the same failure. Probably down to some poor quality engineering process used by the manufacturer of the sensor.

ThilakR · January 10, 2008

Nilantha said:
whats your car model? FB15?

Machan This is SUZUKI Aerio 2003.

Thilak

ThilakR · January 10, 2008

Arc Angel said:
since you took it to A*W i'm assuming this is the sunny with the inherent o2 sensor issue. not sure if our fuel has anything to do with it, but i'm no expert...

Hi..

Thanks for respond.

This is SUZUKI AERIO 2003.

Thilak

ThilakR · January 10, 2008

The Don said:
Might have been, but the FB15 (and even the march of that generation) certainly struggled with the Oxygen sensor on the exhaust manifold.
Another common problem is the cam sensor

The really silly thing about it was that some of these sensor failures caused the Nissans to stop dead but this problem was rectified in later models.

Hi..

Many thanks Guys.

It means the reason they mention is true?

My Car is SUZUKI Aerio 2003. You are very correct. It is fitted to exhaust manifold.

BTW What is the cam sensor?

Thanks god I still do not have any problem on said cam sensor.

I have a manual of this car but it is in Japanese. Therefore no use

Big thank goes to AUTOLANKA too.

Thilak

ThilakR · January 10, 2008

maithri said:
Guys,
O2 sensors fail for many reasons but the warning light comes on mainly when the heater in the sensor is faulty. This is easy to monitor for the ecu so as soon as no resistance is felt it puts the light on but if the car is running ok be careful not to ignore it as the car will start to overfuel and cause premature failure of the cat and lead to excessive wear to the cylinder bores. How ever a cat is not needed in Sri Lanka to stay within the law-so as long as you have no second checking o2 sensor fitted after the cat it is not worth spending money on unless you want to be eco friendly.

The cat does not perform any other function other than cleaning up the gasses emitted by the engine by converting co into co2.

95 octane fuel is common in the west and the O2 sensors generally last around 60,000 miles in good working order. If you test the signal output using a scope you will see the function starting to become erratic much earlier. So I would not blame the fuel unless you see a lot of different models suffering the same failure. Probably down to some poor quality engineering process used by the manufacturer of the sensor.

Hi maithri,

Thank you so much for excellent clarifications. To tell you frankly I was experiencing some unusual performance drop couple of months before of this Check Engine light indication. I discuss this in this forum under "Sudden Performance Drop".

The engineers who check my car said this sensor must be fixed to make the car back in original smooth running and it is true. Now the car is good in fuel too. Also when remove the sensor he checked with a multi meter or something and me too noticed no change in the meter display. So he confirmed the sensor is gone.

What is your advice? If I swith in to 95 OCT will it be helpful to prevent this problem upto some extend?

Thilak

Edited January 10, 2008 by ThilakR

The Don · January 10, 2008

ThilakR said:
Hi maithri,
Thank you so much for excellent clarifications. To tell you frankly I was experiencing some unusual performance drop couple of months before of this Check Engine light indication. I discuss this in this forum under "Sudden Performance Drop".

The engineers who check my car said this sensor must be fixed to make the car back in original smooth running and it is true. Now the car is good in fuel too. Also when remove the sensor he checked with a multi meter or something and me too noticed no change in the meter display. So he confirmed the sensor is gone.

What is your advice? If I swith in to 95 OCT will it be helpful to prevent this problem upto some extend?

Thilak

Thilak,

All the responses I made was with regards to the Nissan FB15 though some of it holds true for all cars

The cam sensor, or the cam position sensor is a sensor which tells the ECU the position of the cam shaft, and some Nissans had a problem of this sensor failing.

Premature failures of Oxygen sensors are caused by impurities in the fuel and is not affected by the Octane figure. What I mean is I do not believe 95 octane fuel is any cleaner than 90 octane so I do not think there is any advantage to be gained by changing over to a higher octane fuel, just to avoid this issue.

ThilakR · January 10, 2008

The Don said:
Thilak,
All the responses I made was with regards to the Nissan FB15 though some of it holds true for all cars

The cam sensor, or the cam position sensor is a sensor which tells the ECU the position of the cam shaft, and some Nissans had a problem of this sensor failing.

Premature failures of Oxygen sensors are caused by impurities in the fuel and is not affected by the Octane figure. What I mean is I do not believe 95 octane fuel is any cleaner than 90 octane so I do not think there is any advantage to be gained by changing over to a higher octane fuel, just to avoid this issue.

Hi ,

Many thanks.

Thilak

prvnrox · December 29, 2011

On 1/9/2008 at 4:04 PM, The Don said:

QUOTE(Ripper @ Jan 9 2008, 09:43 PM)

shiites that sucks... i thought the ECU automatically goes to default settings and gets the job done without the o2 sense providing real time feedback!

Yes even I could not understand why they could not just flash the check engine light and go to default settings and carry on. I think if the after cat oxygen sensor was the one to fail, the catalytic converter failure sign will come up but the car will not stall.

I am quite ashamed to admit this but the catalytic converter failure sign has been on my mirage since the day it was brought due to the failure of the oxygen sensor, but not a single mechanic including Wasantha has taken any interest in replacing it, which is quite frustrating, they all keep passing the ball and making suggestions, and I might have to do the unthinkable, take the car to UM.

Don are u referring to Wasantha at siyoga engineering?? so according to u he is not so good is it?? one of my friends recommended him to me.but when i had a prob with my gear indicator bulb blinking,he never diagnosed it properly he said it is something to do with the gear box but at the end it appeared to be only the speed sensor.Not only wasantha i took it to Randika at 6th mile post too.none of them diagnosed it exept the agents.

The Don · December 29, 2011

On 12/29/2011 at 9:07 AM, prvnrox said:

Don are u referring to Wasantha at siyoga engineering?? so according to u he is not so good is it?? one of my friends recommended him to me.but when i had a prob with my gear indicator bulb blinking,he never diagnosed it properly he said it is something to do with the gear box but at the end it appeared to be only the speed sensor.Not only wasantha i took it to Randika at 6th mile post too.none of them diagnosed it exept the agents.

Well the Wasantha I speak of is a good mechanic and I recommend the man. His workshop used to be on the baseline road but now somewhere inside. I was just complaining about his reluctance to replace a faulty O2 sensor in my car which has clearly failed but does not seem to be affecting the functioning of the car.

But for ECU related electronic issues its always worthwhile to at least go to the agents and get a diagnosis done. There are only a few other experts who are capable and competent enough to handle that sort of work.

prvnrox · December 29, 2011

On 12/29/2011 at 10:06 AM, The Don said:

Well the Wasantha I speak of is a good mechanic and I recommend the man. His workshop used to be on the baseline road but now somewhere inside. I was just complaining about his reluctance to replace a faulty O2 sensor in my car which has clearly failed but does not seem to be affecting the functioning of the car.

But for ECU related electronic issues its always worthwhile to at least go to the agents and get a diagnosis done. There are only a few other experts who are capable and competent enough to handle that sort of work.

how does he look like? any contact of him??

The Don · December 29, 2011

On 12/29/2011 at 10:36 AM, prvnrox said:

how does he look like? any contact of him??

I don't have it with me sadly. He is a rather chubby person and his garrage has the two Mazdas raced by Upulwan Serasinghe as he is his mechanic.

Chaturathi · December 29, 2011

In my honda city 2003 (07 speed model), i also had a faulty O2 Sensor & symptoms were Check engine, engine miss & RPM was below 1000 even fully throttled. This was not always & in every 3-4 minutes & after that it is normal. But friend of mine had a 121 & with Faulty O2 sensor he didn't had any symptom other than bad fuel consumption & check engine. (I didn't notice bad fuel consumption because i attended to it quickly since i was not able to run the car)

upaliamah · December 30, 2011

The Oxygen Sensor detects the amount of oxygen in the exhaust gas and sends a signal to the ECU which adjusts the air fuel mixture to the optimal level.

Too much oxygen in the exhaust gas indicates a lean mixture, which can cause performance problems, including misfires. Too little oxygen indicates a rich mixture, which wastes fuel and results in excess exhaust emissions.

When does an Oxygen Sensor need to be replaced?

Exposure to carbon, soot, harmful gases, thermal and physical shock will shorten the life of an Oxygen Sensor. This results in increased fuel consumption, poor engine performance and excessive exhaust emissions.

Oxygen Sensors with 1 or 2 wires typically have a service life of 50,000kms. While 3 and 4 wire sensors have a service life of approximately 100,000kms.