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emissions failure

502 Views 5 Replies 4 Participants Last post by  dan27
so i have year 2000 bora 1,6 took for mot today and failed on emissions

1. exhaust emissions carbon monoxide content at idle excessive

2, exhaust emissions lambda reading after 2nd fast idle outside specified limits

3. exhaust emissions carbon monoxide content at idle excessive

fast idle test

co 0.11 pass

hc 2 pass

1.045 fail

2nd fast idle

co 0.32 fail

hc 4 pass

1.061 fail

natural idel

co 0.91 fail;

does anybody have any ideas on this one? does smell rich, but no smoke only when starts from cold, i do only do short journeys most the time, will some redex and a good old fashioned blast help?

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Redex might help, but one of those treatments for about £10 - £15 from Halfords & 'an Italian Tune up', just before it goes in to be re-tested (i.e. a good run at motorway speeds (at 70mph, or at least above 50mph so the engine / exhaust get nice n warm), for about 20 - 30 miles / 30 minutes), can make all the difference...

...That said, there's no guarantees... !
You can try a "terraclean" it may fix your emmission.but it's cost about 100 quit and will takeaway 1 hour.

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just plugged me scanner in and got these two codes

00525 oxygen sensor sporadic -implausible signal

00635 oxygen (lambda) sensor heating before cat static -faulty

so im presuming its the lambda sensor on the manifold?
Sorry, but may need a new catalyst. Very similar readings to my wife's polo and no volume of thrashing it before the test or cataclean etc was enough to make a difference. Her engine was in good shape, just a worn out catalyst. The above things are worth a try first though. I certainly wouldn't spend 100 quid on such treatments though when that would be a large proportion of the price of a new cat.

Cheers, Dan
well im gunna take a punt on the lambda sensor 40quid from ecp hope that sorts it for mot , then car must go!
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