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Steve, Vehicle technician
Category: Honda
Satisfied Customers: 1160
Experience:  Garage owner for thirty years
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I have a 2002 (02) Honda Civic 1.6 SE Auto. At MOT time the

Customer Question

Hi, I have a 2002 (02) Honda Civic 1.6 SE Auto. At MOT time the Engine Management Light came on..Failed due to Lambda Sensor failure. It was replaced. The 1 in the engine behind the radiator. The EM light continued to come on and off. Mainly/90% off. So I carried on driving. Now 4 months down the line it is on more than off. Q1 How many Lambda Sensors does my car have/need?
JA: Just to clarify, what are the exact lights you're talking about?
Customer: The yellow light on my dash below the speedo, the sign of the engine
JA: Are you fixing your Civic yourself? What have you tried so far?
Customer: Its in my previous, at MOT time, it failed due to the light and Lambda Sensor. So it was replaced.
JA: Anything else you want the Mechanic to know before I connect you?
Customer: Not really, if it is just to replace the current Lambda sensor which is likely faulty...I can do that myself...
Submitted: 1 year ago.
Category: Honda
Expert:  Steve replied 1 year ago.

Hi thank you for your question my name is ***** ***** I am a fully qualified technician with over 30 years in the trade, hopefully I can help you.

Your Honda has two 02 (lambda) sensors, the one that was replaced sounds as though it was the pre-cat sensor, this controls the switching of the mixture and adjusts according to the reading of the exhaust gasses. The second 02 (lambda) sensor fits in the exhaust after the cat and this is there to read the output of the gasses, this reading should remain steady, if it does not it normally indicates either a faulty sensor or that the cat has failed.

The reason for the light may also be one of the other engine sensors and it would really be best to read off any codes with an EOBD code reader before replacing any components.

This will ensure you are looking in the right area. If the code did come up to be the same sensor, I would advise checking the wiring to ensure the light isn't coming up due to a poor connection to the sensor, this is another common failure.

Finally another common cause of the 02 sensor triggering a code and putting up the light is that an air leak is present in the system.

To answer your question as to whether you could replace the sensor yourself, if it is just the sensor I would say yes, if it is this it will not need coding in, and if it is causing the error code this will be cleared when the new sensor is fitted.

I hope this answers your question but do please feel free to get back to me for any further information.

If this does answer your question please click accept and rate me, this allows me to continue.

I can answer any further questions even after you have done this.

Many Thanks


Expert:  Steve replied 1 year ago.


Just a quick follow up to see if the problem was resolved or whether you needed any further help.

Many Thanks


Customer: replied 1 year ago.
I'm very sorry I just cant deal with this at this time. I am travelling. Your reply did give me a new lead. Air leak. The EMlight came on at the instant I removed a sensor from the Carburettor housing. It was tight, and when I replaced it, it was looser.. I have always felt that this problem may be linked to that. I now feel that more than ever. When I return home I will look to replace that 'housing' rubber gater? Many thanks
Expert:  Steve replied 1 year ago.

Your welcome do get back in touch when you return if needed.

Best Regards