NCT Test - Engine light on

Arist

Hi,

Is the engine light being constantly on a fail in the NCT? My local garage tell me it isn't and tell me to run it through the NCT anyway and see what happens. I suspect the Catalytic Converter is gone but he says it might not be and the best way to find out is do the NCT. However, a family member tells me one of the first things that are tested are the dash lights and if the engine light is constantly on it is an instant fail. Who is correct?

Thanks very much in advance.

John

analfabets

Your mechanic should scan it. It won't fail for light being on but might fail for emissions as there is problem with your engine management system.

Nissan doctor

As above, it won't fail just because the lights is on, but the problem causing the light to come on may be a cause for an NCT fail...i.e cat, lambda sensor etc

unkel

analfabets wrote: »

It won't fail for light being on

Yes it will. At least for a diesel. See the online NCT manual (page 10). If the engine light is on, the won't do a smoke test, so the car fails. Dunno if this applies to petrols too?

Nissan doctor

Page 10 of the NCT manual refers do a diesel smoke test.;)


On a petrol car the light being on isn't a fail or a reason not to test any item.


Dam I should have quoted.....:p

CiniO

unkel wrote: »

Yes it will. At least for a diesel. See the online NCT manual (page 10). If the engine light is on, the won't do a smoke test, so the car fails. Dunno if this applies to petrols too?

But that only applies to diesels

Nissan doctor

OSI wrote: »

He edited the post, it originally didn't say anything about it being diesel only:D

msg11

It's a warning light, it's giving you a warning if it was my car I would be finding out why it's giving me a warning before things go tits up.

Best of luck with the NCT..

Arist

Sorry I should have mentioned it is a petrol car. Thanks for all the replies. My car is 10 years old and I want to spend as little on it as possible. It is a Toyota and the mechanic reckons it might pass the emissions test anyway. If it does and it passes the NCT then brilliant as it has only cost the NCT fee. If it fails on emissions then I will have to start pricing replacing the Cat or maybe even the car. So I think I'll run it rhough the NCT and take my chances.

marryabroad

good to see a decent mechanic. he could easily replace the cat for you and charge you nicely but he isn't. he's doing the clever thing and telling you to put car through test and see what fails, then fix what fails.

it horrifies me how much people spend gettting car ready for nct when chances are they don't need to do half the stuff.

engine light is not a fail. listen to your mechanic.

Nissan doctor

Arist wrote: »

Sorry I should have mentioned it is a petrol car. Thanks for all the replies. My car is 10 years old and I want to spend as little on it as possible. It is a Toyota and the mechanic reckons it might pass the emissions test anyway. If it does and it passes the NCT then brilliant as it has only cost the NCT fee. If it fails on emissions then I will have to start pricing replacing the Cat or maybe even the car. So I think I'll run it rhough the NCT and take my chances.

If it fails on the emissions you'll have to have the cause properly diagnosed not just go straight for the cat. Lots of other things can effect the emissions.

MAYOMICK

I have an 2002 Avensis petrol and the engine managment light is on for the past three years (60000 miles)A scan shows up a lambda sensor.If you remove a fuse in engine bay marked efi this will put the light long enough to do test although as other posters have rightly pointed out this light will not fail a petrol car.My car has passed at least 2 ncts with this problem.I think that there is a heater in the sensor that may be faulty and not the sensor itself.

ofcork

I have a 04 avensis with the eml light on and going for nct next year,was told cat is gone but another garage said emissions were fine so i will nct it and take it from there.

lomb

MAYOMICK wrote: »

I have an 2002 Avensis petrol and the engine managment light is on for the past three years (60000 miles)A scan shows up a lambda sensor.If you remove a fuse in engine bay marked efi this will put the light long enough to do test although as other posters have rightly pointed out this light will not fail a petrol car.My car has passed at least 2 ncts with this problem.I think that there is a heater in the sensor that may be faulty and not the sensor itself.

Why not just replace the lambda? Apart from damaging your car your excess fuel consumption is much more than the cost of the probe.