NCT Emissions

PKWATERFORD

My car just failed the NCT on emissions

CO was 7.92 % (should be below 0.3%)
HC was 635ppm above (0 is a fail)

High idle was

CO 7.89% (above 0.2% is a fail)
HC 365ppm (above 200ppm is a fail)
lambda 0.79 (should be between 0.97 and 1.03)

This looks very bad. Can anyone give me a few pointers before I go to the mechanic so I wont look totally green?

Thanks

Signpost

Year / Make / Model / Milage?

PKWATERFORD

Its a laguna 1.8. petrol 2003 and there are bout 149000 miles onthe clock

itarumaa

Hi,

I would start with this:
lambda 0.79 (should be between 0.97 and 1.03)

and then retest the car and see what is the result.

glanzav69

there are a number of possible causes for this. the simplest one could be a bad set of spark plugs. it could also be your catalytic converter. it could be your lambda sensor which tells the engine management system how much petrol should be injected at one time, if the lambda sensor is defective , it could be over fuelling the engine. if the lambda reading is below the 0.97 limit your car is running rich , if its above 1.03 , your car is running lean. your car will also fail lambda if it has a hole in the exhaust. a lambda sensor measures oxygen content.

vetstu

Give the tester €100 and you'll pass the next time. Works for taxi men.

shawnee

glanzav69 wrote: »

there are a number of possible causes for this. the simplest one could be a bad set of spark plugs. it could also be your catalytic converter. it could be your lambda sensor which tells the engine management system how much petrol should be injected at one time, if the lambda sensor is defective , it could be over fuelling the engine. if the lambda reading is below the 0.97 limit your car is running rich , if its above 1.03 , your car is running lean. your car will also fail lambda if it has a hole in the exhaust. a lambda sensor measures oxygen content.

I would say this information is correct. However there is also an additive sold in many motor factors which greatly improves the emissions. This added to a good long drive and put up a bit of speed will also help:p

shamwari

Those emissions are out by some margin. Was this car driven for a prolonged period in the past with a misfire (no an uncommon complaint with those pencil coils)?

PKWATERFORD

There was a misfire for a bit. Only a few days till I changed the plugs and the coils.

Mechanic is going to change out the lambda sensor and check for holes in the exhaust and try again.

Other than that I might ask for the intermediary that they spoke to on primetime. He sorted everything out

PKWATERFORD

Just to say thanks for suggestions. The car re sat the NCT yesterday and it passed with flying colours.

I just got the lambda sensor changed (involved stripping away most of the engine I am told) and problem sorted right out.

Thanks again

slinky2000

Mine was 300% over last year on both readings, I replaced the lambada and a suspect exhaust and it passed with flying colours