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Rayburn
17-08-2018, 01:42 PM
Hi everyone I am hoping for more advice!
My Beat has failed its Mot due to very high CO emissions. It recorded more than 4% against a limit of 3.5% and I think that it should be able to achieve less than 1%.
The other things measured were close to what they should be so the tester is suggesting that the catalyst is defective.
It would be good to get peoples thoughts on this diagnosis – is there a particular issue with the Beat other than the cat that could give these symptoms? (It is worth noting that the ECU has just been rebuilt).
If I do need a new catalyst is there a source for one in the UK or has anyone successfully adapted one from another car – perhaps an early 1990’s Civic?
Thanks
Tom

stu g
17-08-2018, 10:39 PM
Hi everyone I am hoping for more advice!
My Beat has failed its Mot due to very high CO emissions. It recorded more than 4% against a limit of 3.5% and I think that it should be able to achieve less than 1%.
The other things measured were close to what they should be so the tester is suggesting that the catalyst is defective.
It would be good to get peoples thoughts on this diagnosis – is there a particular issue with the Beat other than the cat that could give these symptoms? (It is worth noting that the ECU has just been rebuilt).
If I do need a new catalyst is there a source for one in the UK or has anyone successfully adapted one from another car – perhaps an early 1990’s Civic?
Thanks
Tom

OK, this could be a number of things:
Are you burning oil?
Was the engine cold when tested?
Is the ECU working properly?
Are the spark plugs working properly - unburned fuel could give a high reading
The cat could be worn out. I'm guessing a new one from Honda is quite expensive. I've never heard of anyone adapting one from another car, but that might work.
Stu

Rayburn
27-08-2018, 07:41 PM
Hi Stu g
Thanks for your advice - sorry for the delay in getting back to you - its been a busy week. You were correct about the engine temperature - I changed the plugs and the o2 sensor and put it in for a retest on Saturday. The tester said that as he let it get properly hot the cat started to work. It achieved a CO result of 0.087% in the end and passed the emissions part of the test.

Which is good as the cheapest price for a new cat I could find was more than $900!

Thanks again.

Tom