Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Please note that it is not permitted to have referral links posted in your signature. Keep these links contained in the appropriate forum. Thank you.

https://www.boards.ie/discussion/2055940817/signature-rules
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Failed NCT due to high emissions

  • 01-06-2004 4:31pm
    #1
    slave1
    Moderators, Sports Moderators Posts: 19,708 Mod ✭✭✭✭


    Hi all,

    My 98 Megane Classic just failed NCT because

    a. my back reg didnt have the county name in Irish :rolleyes:

    b. emissions were 2 high
    low idle 720 rpm
    high idle 2860 rpm

    I'm not car mechanically minded and my mechanic has said about 450/500 for a new cat. Reasonable??

    Can someone put plain english on the emission results, what they should be and possible reasons why they are so high

    As a matter of interest I have no problem making my car acceptable, I just want to understand it all

    Cheers


Comments

  • #2
    mike65
    Closed Accounts Posts: 88,968 ✭✭✭✭mike65


    If your car has a cat the emmissions are ultra-low, once the cat goes its an instant fail. The joke is that your car may still have had lower emissions than a car without a cat like mine.

    The price mentioned sounds about right.

    Mike.


  • #3
    echomadman
    Registered Users, Registered Users 2 Posts: 1,445 ✭✭✭echomadman


    You're not giving enough info on the emmisions there, those are just the engine rpms


  • #4
    mike65
    Closed Accounts Posts: 88,968 ✭✭✭✭mike65


    As echomadman says post the actual emmision numbers.

    My non-cat Merc did the following - @ 810 rpm.

    HC (hydro carbons) 308ppm

    CO 0.15 volumn %

    Mike.


  • #5
    slave1
    Moderators, Sports Moderators Posts: 19,708 Mod ✭✭✭✭slave1


    Okay, the missus dropped the car off and I didn't have the info to hand when I posted thread, I actually have the previous results too
    FYI this is a well looked after car, I don't rally drive and am not a speeder, mostly shortish trips (under 6 miles), 1.6L petrol, manual gearbox, the car was well under in all other categories

    2002 results
    Oil temp 70 C
    Low Idle (1440 rpm) CO 0.02vol% HC 0ppm
    High Idle (3170 rpm) Lambda 1.003 CO 0.02vol% HC 23ppm

    yesterday's results 2 years/15k later
    Oil temp 82 C
    Low Idle (720 rpm) CO 0.81vol% HC 0ppm
    High Idle (2860 rpm) Lambda 0.958 CO 1.59vol% HC 61ppm


  • #6
    Gmodified
    Closed Accounts Posts: 973 ✭✭✭Gmodified


    very poor emission result for car that age. looks like Renault and Citroen have enough problems with the emissions.

    I know guy with Citro Xantia which required major surgery to pass NCT car was relatively new but :

    -computer had to be changed( known issues as fuel management contributed to bad combustion)
    -valve guides had to be replaced
    - cat was replaced

    car barely passed NCT


  • Advertisement
  • #7
    Auslander
    Closed Accounts Posts: 92 ✭✭Auslander


    Hey slave.

    Its quite common for cats to give up the ghost usually at @ 10 year mark

    By the sounds of what you've described,
    I say that more than likely its all the short trips that have done
    the damage.

    The engine never has time to reach normal operating temp,
    the fuel mixture is always running rich.

    In laymans terms all the unburnt petrol in the exhaust gasses
    are passing through the cat, killing it.

    This is also the reason why it is not recommended to push start cars
    with a cat, since the unburnt petrol in the downpipe (exhaust) can also contribute
    to premature cat failure.

    Paddy


Advertisement