Failed NCT on Emissions

user12

Low idle CO .97% above .50 fail
Lambda .75 above .40 fail
High idle CO 9.25 above .30 fail.

What's the likely problem here?

user12

Is this easy fixed? Passed everything else

coylemj

More details please - make, model, year, fuel type, engine c.c.?

user12

Clio. 1.2 petrol. 1999

goz83

Lambda sensor needs replacing by the looks of it, but someone with more knowledge will confirm.

user12

Is the high idle not very high?

user12

Any chance of it passing by just adding a mix into it and driving it hard before hand?

goz83

user12 wrote: »

Any chance of it passing by just adding a mix into it and driving it hard before hand?

Not with readings that off the chart. If the lambda is fecked, the fuel/air mixture is off and no amount of Dipetane and hard driving will fix readings that far off.

user12

Thanks. What do you mean by the fuel/air mixture?

user12

The car was off the road and lying about for a few months. Would this affect it?

goz83

user12 wrote: »

Thanks. What do you mean by the fuel/air mixture?

Without going into the details of it, the engine burns fuel and fire needs oxygen to burn. The lambda sensor controls this when working. Bring car to mechanic.

cletus

Sometimes what appears to be the lambda can be something else. Cat could be gone causing the lambda to fail.

OP, bring it to a mechanic and have it checked

user12

But the lambda is www off as well..will the cat sort this out as well?

Chimaera

Based on those readings, the fuel is not fully burning. There can be a few reasons for this.

Simple things are air filter and spark plugs. Was the car serviced before the test? If it wasn't, get that done first.

Was the car properly warmed up before the test? A cold engine will fail the emissions test.

Then you're into checking stuff like the lambda sensor and catalytic converter.