2.0 NC failed emissions test

Technical Area Engine, Transmission, Exhaust etc
2

My sons 2.0 nc failed the emissions on the Mot today the car does not smoke drives great uses little oil so shocked at outcome mot tester said it needs new engine car has done 125k mileage drives with no rattles or issues i need a pointer where i go from here i did notice on the readout that the engine size was wrong its had a recent oil and filter change and a fuel additive added to the fuel still believed to be in the tank as he only drives local i would be grateful of any pointers

Thanks

3

I think you’ll need to put up the results so people know which bit of emissions it failed as a pointer to the problem.

4

Why a new engine needed, could be the cat or something more simple?

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5

Can you add a photo on these posts so i can show the results

6

Yes scan and save the failed mot cert and emissions sheet and save to jpeg.

Then either upload or load to photobucket type site and link from there.

7

If the engine size on the Print out was incorrect It would surely make the print out Null and Void and as such so would the fail be Wrong Would it not???

8

Not at all Wattie both the 1.8 and the 2 litre engine have to emit exhaust gasses with readings below the same CO and HC level.

9

Result from mot
Fast idle
rpm 2398 pass co 1.812 fail hc 361 fail lambda 0.932 fail
second fast idle
rpm 2468 pass co 2.189 fail hc 365 fail lambda 0.921 fail
natural idle test
rpm 728 pass co 0.489 pass

hope this makes sense
thanks

10

Look for a leak in your exhaust system for the lambda fail I say.

Did your son take it for a blast to heat up the Cat before the test?

11

He went for a blast after the test and they re checked it with the same results

12

The CO tends to suggest a faulty lamda sensor or the MAF is faulty. The high HC figure is a worry.

This particular car needs a lot more than a long run to heat it up!

13

Hi Hillman, was this ever resolved? Same issue my end. I’m devastated after throwing parts at it to no resolution. Also 2.0l mk3 nc.

14

The likelihood of it needing a new engine because of exhaust emissions failure is slim to zero.
The exhaust emissions (before they become emissions) are controlled internally by the ECU, in the petrol/air ratio.
When they’re burnt, then they become emissions, they’re controlled by the catalytic converters in the exhaust.
Sounds like a cat failure.

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