NCT smoke fail - problem caused during test?

MackQ

My turbo diesel failed this morning for excess smoke. Vehicle absolutely 100% fine going in, driving really well and I felt confident about it passing. As it was a sunny morning I would have clearly noticed any smoke behind the car especially as I checked my tyre pressures at the garage on the way in with the engine running.

Felt during the test that that the guy was revving it way too excessively - high revs for well over a minute. I was very conscious of this during the test because there were only two cars in the centre at the time. Failed for excessive smoke.

Started it up and noticed a really strange engine noise and driving out of the centre noticed a thick plume of white smoke behind the car. Returned to the test centre and complained to the person in charge because I felt the problem had been caused during the test. Guy said they had to rev it for the test. Was given complaint form to fill in and he said he would register the complaint. Journey home was a nightmare with massive smoke pouring out from the back of the car. Also have noticed on test report that the engine/oil temperature was 0 degrees C!

Anyone any advice?

Cheers,
MackQ.

MagicSean

The smoke test or emission tests as well as noise test have to be performed at a certain amount of revs. If your car broke at these levels perhaps there is something more serious wrong with it.

pred racer

Unfortunately you also signed a disclaimer before the test, I know it covers your timing belt, not sure about the rest of your engine though.

I've asked before why the test needs to be done at such high revs, because in my car after 3k all you get is more noise! They told me the car has to be able to rev to within a certain percentage of the original manufacturers spec.
Don't know if true or why.

Sorry to hear about your car and I hope you get sorted out.

stephendevlin

Write your complaint and wait for nobody to get back to you

dharn

sounds like your head gasket is gone letting water into the intake manifold

Seweryn

Seanbeag1 wrote: »

The smoke test or emission tests as well as noise test have to be performed at a certain amount of revs. If your car broke at these levels perhaps there is something more serious wrong with it.

No, it is not. The engine should not be held at its maximum revs for a minute :eek: . This is an absolute madness. The engine during the test should be brought to the maximum speed, but the tester should not keep the high revs for any length of time and this is clearly written in the NCT manual available on the website. I would complain and refer to the NCT manual, where it says about the smoke test.

charlemont

Some of these NCT testers are taking the p*ss lately. They are not happy over getting caught out recently.

I Was VB

What was the exact readouts?

langdang

Seweryn wrote: »

No, it is not. The engine should not be held at its maximum revs for a minute :eek: . This is an absolute madness.

He was bouncing it off the limiter for a minute? Or operating it within the normal allowed rev range, but close to upper end?

pred racer

Seweryn wrote: »

No, it is not. The engine should not be held at its maximum revs for a minute :eek: . This is an absolute madness. The engine during the test should be brought to the maximum speed, but the tester should not keep the high revs for any length of time and this is clearly written in the NCT manual available on the website. I would complain and refer to the NCT manual, where it says about the smoke test.

Sorry to go OT. But can someone explain why it has to go to max?
I drive my car fairly hard, even so it never gets anywhere near what they do to it in the NCT (mainly cause there is no point) surely the test should be carried out using a normal range

Bumpstop

I don't understand this either, My owners manual states that " reving the engine with the autobox in neutral or park over 1500 rpm will damage the gearbox".

And is a gearbox fitted to thousands of bmw, Mercedes and Jaguars.

pred racer

pred racer wrote: »

Sorry to go OT. But can someone explain why it has to go to max?
I drive my car fairly hard, even so it never gets anywhere near what they do to it in the NCT (mainly cause there is no point) surely the test should be carried out using a normal range

Only the diesels are reved to the red line, petrols to 3000rpm.

Bumpstop

RoverJames wrote: »

Only the diesels are reved to the red line, petrols to 3000rpm.

:eek: God if I bring in my diesel, they better have a catcher outside with a mit.

MackQ

langdang wrote: »

He was bouncing it off the limiter for a minute? Or operating it within the normal allowed rev range, but close to upper end?

Sustained very high revs over a long period, over a minute in my opinion.

MackQ

pred racer wrote: »

Unfortunately you also signed a disclaimer before the test, I know it covers your timing belt, not sure about the rest of your engine though.

I've asked before why the test needs to be done at such high revs, because in my car after 3k all you get is more noise! They told me the car has to be able to rev to within a certain percentage of the original manufacturers spec.
Don't know if true or why.

Sorry to hear about your car and I hope you get sorted out.

Cheers. I also understood the disclaimer to be a declaration that the timing belt has been changed at the manufacturer's specified interval. Not permission to do other untold damage to the engine...

Nissan doctor

A cars engine and componants are designed to operate up to certain rev limit. This limit is programmed into the ecu by the manufacturer. You cannot over rev a modern healthy modern engine by pressing the accelerator at stanstill...

Unfortunatly, if something failed when reving during the test, it was something that was about to fail on the road anyway.

dharn

would have to agree with that, if you drive for 2 hours the car could be revving constantly at 2000 rpm plus ,if you were standing beside a car revving for 2 hours at 2000 rpm you would expect it to blow up, but other than overheating due to lack of air blowing through the rad it should be able for that, so 4000 rpm for as op said 1 minute ,should be no problem it probably was not a minute just felt like one