19 replies to this topic

[YoungJon]

Okay so just had another emissions test which on 1st idle test failed on the Lambda which is brand new and genuine Bosch,the CAT was OK. Fast idle showed the lambda pass but the CAT failed !!! I'm presuming that at idle the CAT passes but at fast idle it can't clear it due to being clogged . Any ideas other than getting the CAT changed ?

[R32Egor]

HI,

I have an SPI that had problems but i am not sure how similar the 2 are but -

 

In an SPI unless the engine temperature has reached 88 degrees then the lambda closed loop circuit does activate. Which is why when I go for TÜV (MOT) emissions test I have a well driven hot engine to make sure the Lambda sensor circuit is activated and so controlling the idle/emissions.

 

In an SPI this closed loop is active at idle and at a constant revs (crusing).

 

So I presume it is at Temperature.?

[YoungJon]

Hi guys. It has been a while since my last post on the on going emissions problem. I have been told by someone who worked at J Cooper garages, he said that when Rover were developing the MPI they struggled to get emissions down to acceptable levels.Original MPI back boxes are huge and it's for a reason . It's to stop the pulsing of the exhaust which is down to the cylinder head porting apparently and the fuel injection of the engine. This guy told me that when testing an MPI for emissions he always pushes a damp rag along side the exhaust probe up the tail pipe of non standard back boxes to stop the drawing in of air that screws the exhaust gas test! I have not tested this out so I have no proof that this works but, I have no reason to doubt the guy who has his own classic mini workshop.
John .

[cal844]

Hi guys. It has been a while since my last post on the on going emissions problem. I have been told by someone who worked at J Cooper garages, he said that when Rover were developing the MPI they struggled to get emissions down to acceptable levels.Original MPI back boxes are huge and it's for a reason . It's to stop the pulsing of the exhaust which is down to the cylinder head porting apparently and the fuel injection of the engine. This guy told me that when testing an MPI for emissions he always pushes a damp rag along side the exhaust probe up the tail pipe of non standard back boxes to stop the drawing in of air that screws the exhaust gas test! I have not tested this out so I have no proof that this works but, I have no reason to doubt the guy who has his own classic mini workshop.
John .

Have seen this on a few minis. It can draw air from the tailpipe, only way to test is to block the gap around the probe.

Worth a try IMO. Can we see the emissions data from your MOT?

Edited by cal844, 08 February 2023 - 09:10 PM.

[YoungJon]

Fast idle test .
CO % VOL 0.90
HC ppm VOL 147
LAMBDA 1.07

Edited by YoungJon, 09 February 2023 - 05:38 PM.