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MOT failed on emissions

Car failed MOT on CO emissions today, CO 0.68% HC 145ppm, O2 1.11%, LAMBDA 1.03. They are trying a new lambda sensor, when I got home I noticed the oil temp reads 20 C, surely this is far too low? Could this be the reason for high CO reading?

Asked on 20 October 2011 by zippyone

Answered by Alan Ross
Well yes you are correct in that the oil temp should be 70.C
As for the other readings
Your Lambda reading should be 0.97- 1.03(at increased idle speed)
Your CO reading should be 0.5 (at idle speed) HC at 100PPM
Your O2 level should be at 0.1 to 0.5 at idle speed.
Would suggest that you ask the garage to re test ( at no extra cost) at the correct oil temp.
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