Flex pipe leak cause emissions fail? Clubman R55 1.6 Petrol.

Flex pipe leak cause emissions fail? Clubman R55 1.6 Petrol.

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mikeote

Original Poster:

10 posts

61 months

Tuesday 1st October 2019
quotequote all
Heya, thanks for checking out my thread.

I have a 1.6 petrol 67k miles 2010 Clubman R55 which just failed it's MOT on emissions. The previous MOT (three months ago) picked up an exhaust leak from the flexi pipe part of the exhaust near the engine as an advisory (passed that MOT) but the MOT completed today didn't pick up that leak; they just failed it on emissions of CO being too high.

Can the flexi pipe leak (before O2 sensor) cause the O2 sensor to tell the ECU that there's insufficient fuel being injected? Leading to the engine running too rich and pushing out too much CO? The car seems to run fine and there are no codes stored. I currently only have a cheapo scan tool so can't see proper engine data.

The reason for a second MOT after just three months is that I'm I wanted to have no advisories as I'm intending to sell the car, I fixed the other advisories it had.

The mechanic i spoke to said that the timing chains stretch on these which can cause too much CO to be pushed out, though I have no rattling or other chain noises.

Cheers!
Mike

E-bmw

9,979 posts

159 months

Wednesday 2nd October 2019
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I don't know why you would bother trying to "remove" advisories, anyone checking the MOT history of the car on DVLA website will see them still, you now have advisories & fail registered in the online data for your car & also a bill to sort out the problem.

But, yes an exhaust leak can cause emission failures.