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MOT Emissions Failure


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HI Guys, 

Big mistake not running the car much and dropping it in for its MOT test. I had thought that giving it a spirited driver before hand would be enough. The up shot is a major failure. I've posted the readings which are the best of the banks. Lambda was way out and the higher the revs the worse it got, up to 1.357. have a look at the results I'm guessing that the CATs are ok as the CO and HC are low?

I'll check the:  Lambda sensors via OBDII, Clean the K&Ns filters and Check the exhaust for leakage....anything else?

I replaced the battery and recharged the A/C which meant that I had to reset the relearn idle on the ECU. Did the standard relearn x3 cycles the a/c on then 40mph for the required time. To be fair the A/C did when switched on did cause the idle to drop and take a few cycles to get balanced. Do you think that this could still be effecting the emissions?

thanks in advance Steve 


MOT emissions.JPG

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The car is booked in on Saturday for the emissions retest having checked the filters and found them to be a little dirty.  So cleaedn and oiled them, first time I've done it in 4K miles and 8years since fitting them. 

Next check was the OBDII and the O2 sensors which are operating as they should. 

Next was checking the cats and the exhaust for leaks. Slight blow between the silencer and the cat so used the exhaust gum. Then found the my cat has a crack which I've repaired using the gum. That said I'll speak to Pete @pnm as I would not have expected the stainless steel to crack as only a few years old. 

The last check was the cat to turbo and again a slight leak. So gummed it up. 

I'll let you know the outcome on Saturday. Thanks all. 

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