When the car passes the MOT there are a set of emission figures attached, giving a pass/fail reading within a set of parameters.
Can the readings indicate that any item/function/component/sensor might be in need of replacement ?
For instance, in Feb my Forester (EJ20G engine) passed the MOT and the figures were.....

Fast idle

CO .300%
HC 30 ppm
Lambda 1.022

Natural idle

CO .387

Now what does this mean, the car is obviously within the set figures but do they give a clue as to anything else ?
Is there something that will shortly require attention ? Anything that needs adjustment now ?

Thanks

JBL

 

0.3 and 0.387% CO are a bit high, could be a catalyst issue. or it might just not have been quite as hot as it should have been.

30ppm is good, but liklewise a little on the high side.

Lambda 1.022 is fine.

I suspect they ran the car up after it was standing for a while and tested it as soon as the cat was hot 'enough'.

Simon

 

Thanks Simon,
Yes they did. Had to get it hot to pass the tests, was on a very fast idle for a good while.

Cheers

JBL