Nct failed on emissions

Gavpoolking

Hi my car failed on emissions at the nct on December 12 2014 low idle was 2.78 vol% anything above 0.50 vol% is fail and 0.56 vol% on high idle 0.30% is fail would living only a 2 minute drive from the test centre have anything to do with it as car was ice cold as it was a freezing morning test was at 08.45 and ice covered car I also drive to work everyday stop start rush hour traffic never gets a run on the motorway could given it a run on motorway help?????also added a litre of diptane last week to help any suggestions would be great re-test end of January car is a Renault meganne 2000 last years nct was 0.0vol% on emissions but live in Wicklow then and always had car on motorway .... Would appreciate any suggestions or diagnosis ....... Many thanks

demanufactured

Bring it for a long drive beofre the next test.

SEPT 23 1989

lambda sensor

shawnee

Exhaust leak can also affect emmissions, could be a simple repair.:pac:

Leydo10

Petrol usually fail. Either HC or CO2. If HC check lambda/cat hole in exhaust and oil consumption. Oil being burnt = high HC. CO2 you need a system cleaner... BG 44k will clean entire fuel system and drop CO2 as mentioned drive like you stole it after using.... If burning oil flush engine oil/drain and put BG RF-8 in with new oil... Swells valve seals and conditions oil... It's a bandage for poorly serviced cars but will stop you burning oil...

kevohmsford

I had the same problem with a diesel engine. Put in a drop of dipetane and drove it hard before re-test. Passed no problem.

Agricola

Same problem recently too. Older car which needed the carb tuned, also used a half bottle of diptane in the fortnight before the test. Emissions results were cut by about 70%
Was continually told by everyone to get cat checked but car didnt have one. Good luck.

Leydo10

Failed on diesel??? Emissions? Diesels don't fail because of emissions its a black smoke test?

Leydo10

Petrol have Cat diesels have DPF

heldel00

My dad failed three times on emissions (01 petrol bora). Lucky enough he got the same tester on last two occasions and he took pity on him. He absolutely revved the shíte outta it and it passed by the tiniest percentage.

Leydo10

Irish people don't know how to drive..., cars meant to be driven!!! Diesel needs proper drive at least once a week for 50km hard!!! Petrol the same!! It's good for the engine!! I'm constantly looking at emission failures for 1- lack of servicing ( you can't reverse 10 years of neglect in one service) 2- not being driven hard enough. 3- diesels should not be city driven ( buy a petrol)

Gavpoolking

Had car in today drove it in third and forth gear hard up the motorway for 20 mins before test car PASSED!!!emissions were 0.00% vol on high and low idle I'm sure the diptane helped too that I put in 10 days before test very happy and no mechanic involved easy fix