MOT Fail: Carbon Monoxide at Idle and 2nd Fast Idle!

[t-tony]

Can you post the emission test results please?

Tony.

 

[t-tony]

New equipment in the market now which is much improved we have a number of centres running the bosch bea 950 analysers.
They plug into obd and everything is bar graphs on the screen so reads oil temp , engine revs etc through obd and wont let test proceed unless oil temp correct and during test ( petrol) revs must be kept between the graph lines or countdown timer resets.
On diesel same oil temp check then governer check ( this machine will make you rev the diesel to its set govener before allowing test commencement)
Then on print it will show for each rev
The oil temp , idle speed , max rev at limiter also how long it took to take rev to limiter and how long held .
When you rev it the revs show red on screen got to keep going till goes green .

As for the readings above without knowing the oil temperature difficult to make a proper judgement.
But lambda is low ( ideal is around 1.01 ) low is rich high is lean.
With reading as high as that at idle it would smell rich a good running 2.8 single or twin vanos should be good just mot'd a 2.8 single vanos with 120k emissions were spot on .
The tu 2.8 is a euro 3 engine so has 2 cats ( cyl 1 to 3 and 4 to 6 ) with 4 lambda 2 pre and 2 post cat then a y piece to merge to one and at rear a valved back box these are usually spot on for emissions

Do you have a code reader if so check for faults.
If nothing then may just be needing to get everything back to proper operating temperature to clean it out.

Stephen.

I've not heard about these emission testers using OBD port Steve, it makes sense, until you consider it is not really any different from the first Cat testing where you hooked up a Tachometer and an oil temp. Sensor to the motor and had to keep the revs in the green range to keep the test “live”.
I can see the same problems arising with engines overheating in some cases to be honest.

Tony.

 

[as400]

It was one of the front sensors...replaced with a Bosch sensor £92

 

[t-tony]

Cant fault those results!

Tony.