Mondeo failed MOT - emmissions... (lambda reading)

Stevie 22 years ago

Any advice appreciated...

Have a '94 M CO: %vol - 0.00 HC: ppm vol - 013 CO2: &vol - 13.39 O2: %vol - 2.48 Lambda: 1.131

Tester said lambda readings failed test. Car was idling rough and have since replaced the Idle Air Control Valve which has smoothed that out.

Exhaust had 2 small 'blows' & have since sorted that out.

Have just serviced the car (although it was last seviced just 8,000 miles ago).

Lookng for any other suggestions, from gas tester readings, as to any other electronics that may need replaced.

I don't have any local diagnostic centres, although there is a Ford centre about 25 miles away which I'll go to as a last resort...

TIA.

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Stevie 22 years ago

As with most MOT stations - really big thanx for the post! :)

"Enough" could be more than the car's worth in a few cases though...

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Kris 22 years ago

Either an air leak on the car or the analyser. Take it to another MOT station and ask nicely for a gas check. The O2 is far too high causing the high lambda. Looking at the CO and HC, the Cat's ok.

Chris

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k.simons 22 years ago

Hello,

Pay them enough or take it to the right garage and it will pass.

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Tim (Remove NOSPAM. 22 years ago

Yes- the OP mentions he had an exhaust leak- this would be introducing o2.

Agreed.

Bet it now passes fine with the renewed ISCV and leak free exhaust.

Tim..

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Steve B 22 years ago

I tend to agree also. I had an exhaust with tiny pinholes in the back box pipe weld which caused similar lambda and O2 readings. A new exhaust fixed it, but I expect a wipe of gun gum would have done the same.

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