NCT Testing BMW's Incorrectly

DHFrame

Just want people to know to be careful with NCT test centers testing BMW emissions incorrectly.

I just had my 2008 BMW 118i tested in Naas and it failed on emissions.

It read.

High Idle (2,815rpm) Lambda: 0.96 (not between 0.97 and 1.03) fail
CO 1.39 vol % (above 0.20%) fail

I did a bit of research. So for starters, it was tested at a too high rpm, should have been tested at 2500 - 2700rpm.

Limits set by the Emissions 17th edition paper (which the Irish government follow also) states my vehicle should have passed with flying colours - even at 2800rpm.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/194133/Emissions_17th_Edition.pdf

Paper says:

High Idle (2700rpm max) Lambda: 0.7 min to 4 max. PASS
CO max 2.0 vol % PASS

I am going back in and I am going to ask for my Expenses to and from center and phone calls to BMW and loss of earnings returning back to show them a sheet of paper telling them how to do there fecking job.

Pull yer ****ing finger out lads.

Tzardine

Prepare for a massive amount of shoulder shrugging I suspect.

Good luck. Keep us updated.

MarkR

I think they best they will offer is a free retest. I don't think consequential losses are really covered. I wonder how they decide what rpm to run it on? Does their software offer it based on the reg?

hi_im_fil

You do realise the document you linked is an English document? And has no standing as far as NCT is concerned?

Your Lambda is a fail straight off anyway, it doesn't matter what rpm it is tested at.

Check the relevant Irish NCT document which states how to test the car. I'm pretty sure it doesn't have an exact rpm range to test the emissions at.

DHFrame

MarkR wrote: »

I think they best they will offer is a free retest. I don't think consequential losses are really covered. I wonder how they decide what rpm to run it on? Does their software offer it based on the reg?

Well this is one of the points BMW have brought up. They should not be entering Reg Numbers into the system. It should Chassis number and engine code. If they are entering reg only then the system can just choose a generic setting.

DHFrame

hi_im_fil wrote: »

You do realise the document you linked is an English document? And has no standing as far as NCT is concerned?

Your Lambda is a fail straight off anyway, it doesn't matter what rpm it is tested at.

Check the relevant Irish NCT document which states how to test the car. I'm pretty sure it doesn't have an exact rpm range to test the emissions at.

You are wrong. How has it failed? It should be tested between 0.7 min to 4 max

Read the post again buddy.

hi_im_fil

DHFrame wrote: »

You are wrong. How has it failed? It should be tested between 0.7 min to 4 max

Read the post again buddy.

You are getting your information from an incorrect source.

Correct source: http://www.ncts.ie/NCT%20Manual%20Revise%20May%202012.pdf

See page 14:

Lambda -
"3 For vehicles first registered on or after 1st day of January
1994, the lambda value at 2,500 rpm or at the speed
specified by the vehicle manufacturer is not 1 ± .03 or
within the vehicle manufacturer’s recommendation"

challengemaster

DHFrame wrote: »

You are wrong. How has it failed? It should be tested between 0.7 min to 4 max

Read the post again buddy.

Based on what facts?

The way cars are tested is laid out in the nct manual. How about trying to fix issues with your car rather than with the test.

DHFrame

hi_im_fil wrote: »

the lambda value at 2,500 rpm or at the speed
specified by the vehicle manufacturer is not 1 ± .03 or
within the vehicle manufacturer’s recommendation"

or within the vehicle manufacturer’s recommendation
or within the vehicle manufacturer’s recommendation
or within the vehicle manufacturer’s recommendation

FROM BMW Lambda: 0.7 min to 4 max. PASS

hi_im_fil

DHFrame wrote: »

or within the vehicle manufacturer’s recommendation
or within the vehicle manufacturer’s recommendation
or within the vehicle manufacturer’s recommendation

FROM BMW Lambda: 0.7 min to 4 max. PASS

Where is it stated that BMW accept those limits?

DHFrame

hi_im_fil wrote: »

Where is it stated that BMW accept those limits?

I have just been told it by BMW in Rathangan over the phone. I will give you the evidence once I receive the document via email.

Jesus.

CountingCrows

DHFrame wrote: »

Jesus.

Our Lord has returned, and he's driving a BMW 118i :eek:

DHFrame

CountingCrows wrote: »

Our Lord has returned, and he's driving a BMW 118i :eek:

Clown.

Lambda document attached for the little angry people in the world.

hi_im_fil

Interesting. Let us know how you get on.

DHFrame

And just to let you know. @ 2815 rpm that they tested it at - that will push the CO far to high for the test.

listermint

It appears some apologies are in order...

CountingCrows

DHFrame wrote: »

Clown.

Lambda document attached for the little angry people in the world.

There's only one angry poster in this thread.

biko

DHFrame, cop on and mind the language

pippip

Wear this when you go back into them.


Will be interesting to see their response to it all.
Its a fairly automated system so I wouldn't imagine they could just hit a PASS button for the Lambda reading. I wonder if they use the correct chassis number does the limits alter to the .7 and 4 in the system.
As mentioned getting them to use the correct rpm would be job one.
I wouldn't mess around, ask for the manager/supervisor immediately before speaking to anyone.

dougie-lampkin

Are you sure the BMW Lambda readings are measured in the same way? A Lambda reading of 0.7 would give an A/F of 10:1, I'd be surprised an engine could run on that. Likewise, a Lambda of 4 would give an A/F ratio of 60:1, which would easily melt a hole in a piston. Could the BMW values possibly be voltage readings off the O2 sensor or something? They look like the min/max values the sensor can read, rather than the acceptable limits. 60:1 (λ = 4) is off the scale lean, there's no way to consider that acceptable.

Every production petrol car tries to get a Lambda reading of 1, which is an A/F ratio of 14.7:1, the optimal fuel to air ratio for a full burn of petrol. BMW haven't changed the physical properties of petrol, so a Lambda of 1 is still what should be measured. They did throttle it too high, but that's not affecting the Lambda reading. 100 RPM less will also not bring the CO down far enough to pass. Your car is running rich, get that seen to and stop blaming the NCT. Demanding your "expenses" and loss of earnings back is laughable, that's energy better expended by, y'know, fixing the car and getting it retested.

pippip

dougie-lampkin wrote: »

Are you sure the BMW Lambda readings are measured in the same way? A Lambda reading of 0.7 would give an A/F of 10:1, I'd be surprised an engine could run on that. Likewise, a Lambda of 4 would give an A/F ratio of 60:1, which would easily melt a hole in a piston. Could the BMW values possibly be voltage readings off the O2 sensor or something? They look like the min/max values the sensor can read, rather than the acceptable limits. 60:1 (λ = 4) is off the scale lean, there's no way to consider that acceptable.

Every production petrol car tries to get a Lambda reading of 1, which is an A/F ratio of 14.7:1, the optimal fuel to air ratio for a full burn of petrol. BMW haven't changed the physical properties of petrol, so a Lambda of 1 is still what should be measured. They did throttle it too high, but that's not affecting the Lambda reading. 100 RPM less will also not bring the CO down far enough to pass. Your car is running rich, get that seen to and stop blaming the NCT. Demanding your "expenses" and loss of earnings back is laughable, that's energy better expended by, y'know, fixing the car and getting it retested.

But according to his figures from BMW his current Co2 figure is still a pass.

Kenny Logins

0.7 - 4 !?

Is it not 0.7 - 1.04 or something?

dougie-lampkin

pippip wrote: »

But according to his figures from BMW his current Co2 figure is still a pass.

I don't know what you're looking at, but both the NCT manual and the BMW figures say above 0.2% is a fail.

pippip

Kenny Logins wrote: »

0.7 - 4 !?

Is it not 0.7 - 1.04 or something?

If you open the Uk doc the op references it gives the exact figures for each model. The other two 118i engines are .7-1.03 but the specific engine the op has is listed as .7 - 4.

Kenny Logins

pippip wrote: »

If you open the Uk doc the op references it gives the exact figures for each model. The other two 118i engines are .7-1.03 but the specific engine the op has is listed as .7 - 4.

Yeah, just reading now about titania oxygen sensors.

http://www.bmwownersclub.com/forums/topic/4369-lambda-sensors/

pippip

dougie-lampkin wrote: »

I don't know what you're looking at, but both the NCT manual and the BMW figures say above 0.2% is a fail.

Ah yes, I hadn't checked the co2 figures in his UK Doc

kona

DHFrame wrote: »

or within the vehicle manufacturer’s recommendation
or within the vehicle manufacturer’s recommendation
or within the vehicle manufacturer’s recommendation

FROM BMW Lambda: 0.7 min to 4 max. PASS

if you had 4 lambda i doubt your car would be running. I wouldnt be so quick to run in there telling them how to do their jobs unless I was 110% right, in otherwords Id have it tested on another machine at the right RPM.

Those figures show your car is running a bit rich, what temperature was the oil when it was tested?

ninty9er

What are the odds the OP drove to the NCT centre without giving the car a good warm up.

Cosmo K

The OP is right, there is an exemption for newish BMW petrols,. You have to check the cars chassis number, to be sure the car falls within that bracket. The problem is, they are so few, newish petrol BMW's out there, its easy to forget that there is an exemption for them, its all diesels nowadays....

burke027

The problem with your engine is a blocked breather valve my friend.fix it and u will pass

slimjimmc

DHFrame wrote: »

Well this is one of the points BMW have brought up. They should not be entering Reg Numbers into the system. It should Chassis number and engine code. If they are entering reg only then the system can just choose a generic setting.

I doubt that. I believe the NCT's vehicle database is taken from the Dept of Transport's National Vehicle and Driver File which has the details of every vehicle registered in Ireland. There is no need to enter VIN/Engine numbers since all that information can be retrieved using the reg number alone.

However that doesn't mean that NCT's system has been given the correct manufacturer limits specific to your vehicle or that mistakes haven't been made somewhere.
Perhaps verify the physical stamps on the car, your reg documents and the NCT report all have the same VIN/engine number.

Matt Simis

pippip wrote: »

If you open the Uk doc the op references it gives the exact figures for each model. The other two 118i engines are .7-1.03 but the specific engine the op has is listed as .7 - 4.

Kenny Logins wrote: »

Yeah, just reading now about titania oxygen sensors.
http://www.bmwownersclub.com/forums/topic/4369-lambda-sensors/

Right.. so the BMW guideline is referencing a Titania sensor.. which makes that value irrelevant as NCT use their own sensor. Also I fail to see how a manufacturers accepted tolerance for any sensor or emissions part trumps a Government required quality target.

George Dalton

As another poster already said the CO limit according to BMW and according to the VOSA in the UK is 0.2%

Since the OP's car recorded a figure of 1.39% it would seem that there is something wrong with the car.

Having said that the lambda figure certainly should have passed so the NCT have some explaining to do.

Interslice

George Dalton wrote: »

As another poster already said the CO limit according to BMW and according to the VOSA in the UK is 0.2%

Since the OP's car recorded a figure of 1.39% it would seem that there is something wrong with the car.

Having said that the lambda figure certainly should have passed so the NCT have some explaining to do.

Lambda: 0.96 (not between 0.97 and 1.03) fail
CO 1.39 vol % (above 0.20%) fail

Looks to me like they made the right call. Car appears to be running a bit rich. Them bmws figures look far too extreme to ever fail a test.


From the mot manual the OP posted, it would have failed that too.

The emissions limits to be met are specified for both the fast and normal idle tests.
At fast idle, CO must be at or less than 0.2%, HC at or less than 200 parts per million
(ppm), and the lambda value(1)
must be between 0.97 and 1.03. At normal idle, CO
must be at or less than 0.3%.

although it does mention it here for certain engine codes

116i 3 & 5 door Engine Code N43 B16 A 0.2 870 0.2 200 0.7 4 2700 60 2300 680
116i 3 & 5 door Engine Code N43 B20 A 0.2 870 0.2 200 0.7 4 2700 60 2300 680
116i 5 door Engine Code N45 B16 A 0.2 850 0.2 200 0.97 1.03 2700 60 2300 600
118i 5 door Engine Code N46 B20 B 0.2 850 0.2 200 0.97 1.03 2700 60 2300 600
118i 3 & 5 door, Convertible Engine Code N43 B20 A 0.2 870 0.2 200 0.7 4 2700 60 2300 680
120i 5 door Engine Code N46 B20 B 0.2 850 0.2 200 0.97 1.03 2700 60 2300 600
120i 3 & 5 door, Coupé / Convertible Engine Code N43 B20 A 0.2 870 0.2 200 0.7 4 2700 60 2300 680

Duke of Speed

there are 2 different voltage reading lambas fitted to all cars narrow band sensors,and wideband sensors which are the more modern sensor fitted to newer cars. narrow band lambda is a 0 to1volt sensor and wideband is a 0 to 5volt sensor narrow band has a small range around 14.7 afr which is total combustion of the fuel which is universally known as lambda 1 or stoich and in ideal conditions is achieved between 0.97v and 1.03v on a narrow band and should achieve under 0.3 CO% the wideband has a wide range of 8afr to 22afr which is used universally to map cars and has a finer resolution and reacts faster to keep the emissions in check so the range in voltage is .7volt to 4volt 3.7volts is roughly 14.7 afr or lambda 1 and now you can see the differences of 0.97 to 1.03 and .7 to 4v both achieve the one emissions under 0.3 which is the pass rate or lamda 0.97 to lambda 1.03 which is the tolerance as the poster dougie said so the op is quoting lambda voltage for his car which has a wideband lsu bosch sensor older lambda sensors have a life of approximately 60k miles your car has a fault and if you check the live data on a scan tool it will give the voltage of the lambda to see is it working correctly bmw have either lambda as shown by the chart of models hope this helps

hi_im_fil

But the nct test use their own sensor which gives the lambda reading. They don't rely on the BMW sensor. So it should still be within the 0.97-1.03 range as far as I can see.

Duke of Speed

the nct uses a 5 gas analyser which every garage and car manufacturer use even central heating oiil bolier techniciians to measure the emitting gases the lambda sensors help achieve these results. the lambsa sensor feeds a signal to the ecu so the ecu can achieve these standards the nct does not test the bmw sensor it tests the emissions as i said lambda 1 is a measure of enissions

George Dalton

The OP is not quoting voltage. They are quoting the actual lambda spec for their car (assuming it is the N43 engine) of 0.7-4.0.

Duke of Speed

there is no such thing as lambda 4 in emissions i map cars for a living and have to achieve these values to pass nct what bmw are quoting in there specs are the operating voltage that the ecu uses from a 5v lambda which is a sensor all tuners use no rocket science here. this bmw guy has a fault and if he brings it to a garage it can be fixed i deal with this problem every day as does every other garage

George Dalton

The BMW N43 engine is a lean burn engine and has a much wider lambda spec than any other engine I know of. Lambda figures of 2-2.5 are perfectly normal.

You don't have to take my word for it. If you deal with this every day then you should have access to Autodata or similar. Go on to Autodata and look up the emissions spec for a BMW with an N43 engine. It clearly says 0.7-4.0 whereas practically every other petrol engine is 0.97-1.03 as you say.

Now all of this doesn't take away from the fact that I still reckon there is something wrong with the OP's car. That CO figure of 1.39% is way too high. For all we know the OP's car may not even have the N43 engine, it could have the N46 which does operate within the normal lambda range of 0.97-1.03.

Duke of Speed

most cars george have wide band lambda the 1.8t lambda is the sensor used by innovate motorsport widebands they work from 8afr to 22 afr but your only need 14.7 to 16afr for cruising emissions the wide band only gives the ecu the scope to read wider ranges and react faster and more stable for can bus on the newer cars to achieve better control. any fuel, ethanol included at stoich gives lamda 1 but the afr differs, bmw is no different to any other car using wideband as i said i map them. this thread is about a guy who says the nct are wrong which he is going to find out is not the truth he obviosly does not understand the emissions test ask any tuner with a rolling road if lambda 1 is 14.7 lambda 2 in theory would be an afr of 29 to 1 which is 29 parts of air to 1 part of fuel the engine would not run right and burn pistons lean burn engines run between 15 and 16.5 to 1 afr non turbo because of detonation

George Dalton

You don't need to explain to me about AFR or wideband lambdas believe me.

Lose the condesending attitude and look up the emissions specs for the N43 engine and then come back on here and tell us what it says.

Duke of Speed

george i have no condesensending attitude i speak facts and have no interest in offending anyone i came on here to participate in a discussion on this thread and provide answers thats what this site is here for i believe but theres always personal nastiness around, mods warned a poster already on this thread, its not a besting match, maybe we should tell the op whats wrong with his car plenty posters have given there opinion i gave mine bmw say under .2 co% no differnt to any other car, this car is over 1% fail

George Dalton

When I first read this thread I had the same opinion as you. Then I did some research and realised I was wrong in my opinion.

Have a look at the attached picture. I took a screenshot of the N43 emissions specs from Autodata.

Duke of Speed

ok george i see what your saying the 0.2 is the important one here which is the emissions we all agree on that. The 0.7 to 4 is lambda stated in voltage range. an awful lot of people mix lambda 1 unit as opposed to lambda voltage if i stick a voltage meter into sensor signal wire on this model the voltage should fluctuate between 0.7 and 4v to be in tolerance of ecu limits, to give me 0.2 co% so these facts are correct george if i go to another bmw with a narrowband 1v lambda it will be .97 to 1.03 to achieve the 0.2co% lambda voltage and lambda are confusingly different. until you get your head around it it took me time to, when studying it george

djimi

Any chance you could punctuate your posts Duke? Its very hard to read a block of unpunctuated text like that.

Duke of Speed

djimi wrote: »

Any chance you could punctuate your posts Duke? Its very hard to read a block of unpunctuated text like that.

my apologies djimi not good with typing will do in future

Old diesel

Looking forward to hearing the eventual outcome with this - whatever it is - fault with car - or with NCT

Very interesting stuff

Duke of Speed

Old diesel wrote: »

Looking forward to hearing the eventual outcome with this - whatever it is - fault with car - or with NCT

Very interesting stuff

it would be great if the op told us what diagnostics he has done on the car. and if its logging faults, otherwise its back to basic electronics to fix it. tThese cars are well known for throwing up faults where the fault is not the obvious sensor

dougie-lampkin

George Dalton wrote: »

The BMW N43 engine is a lean burn engine and has a much wider lambda spec than any other engine I know of. Lambda figures of 2-2.5 are perfectly normal.

You don't have to take my word for it. If you deal with this every day then you should have access to Autodata or similar. Go on to Autodata and look up the emissions spec for a BMW with an N43 engine. It clearly says 0.7-4.0 whereas practically every other petrol engine is 0.97-1.03 as you say.

Now all of this doesn't take away from the fact that I still reckon there is something wrong with the OP's car. That CO figure of 1.39% is way too high. For all we know the OP's car may not even have the N43 engine, it could have the N46 which does operate within the normal lambda range of 0.97-1.03.

Is it possible it's an incorrect figure from BMW for the N43 engine? BMW haven't changed the physical properties of petrol, an AFR of 60:1 is in no way acceptable, lean burn or not. And if it is a lean burn engine, why does it consider as rich as 10:1 acceptable? You'd be pushing visible lumps of carbon out of the exhaust at 10:1. It sounds to me like 0.7 - 4 is the sensor's range, not the emissions limit, and it's been mistakenly published as the emissions limit.

Kenny Logins

dougie-lampkin wrote: »

It sounds to me like 0.7 - 4 is the sensor's range, not the emissions limit, and it's been mistakenly published as the emissions limit.

I thought that was established already, or am I getting confused again? :pac: