M.O.T. emissions - FAIL?

[Ianmc]

A bit of a thread revival i'm afraid.

My Z3 (1.9 M44 engine code: 19 4S 1) failed MOT on CO emissions this morning. HC and Lamba readings were well within limits.
Car had similar failure last year. Fitting a new cat fixed the emissions then (done as part of a MOT as part of the buying process).
This year the fast idle test was 0.53 (limit is 0.3), natural idle was 0.710 (limit is 0.5). Engine was fully warmed up.
So, unless the year old cat has failed, it must be something else. Think there is a sensor or the EMS could be playing up?
Have booked car into my trusted indy next week to diagnose.
Any experience of this in the meantime would be interesting please?
Thanks,
Ian
PS: good news is that the car was complemented on is rude health and originality in every other department.

 

[t-tony]

Look into if the Cat which was fitted had only a year warranty Ian, some do some have 2 years. Most likely the car at fault but did they test it properly?
Can you post a picture of the emissions failure printout?

Tony.

 

[Stevo7682]

Could be the cat if it's a cheap one

 

[Ianmc]

Could be the cat if it's a cheap one

I'm sure it was indeed the cheapest one the dealer could get in order to get the car sold!

 

[Ianmc]

Look into if the Cat which was fitted had only a year warranty Ian, some do some have 2 years. Most likely the car at fault but did they test it properly?
Can you post a picture of the emissions failure printout?

Tony.

Hi Tony,
Think they tested properly. Its a MOT testing centre, privately run and owned, that I have used for 20 years with many cars. I observe what he checks closely (for personal interest), trying not to get in his way!! He did all he could to reduce the reading but it was not coming down!
Printout posted. Unfortunately, don't have information about the cat fitted as it was done before I took delivery. Will try the selling dealer if it proves to be a cat failure, but don't hold out much hope though.

 

[t-tony]

Sorry Ian he did not test it properly. The oil temperature was by passed.

Tony.

 

[Ianmc]

Sorry Ian he did not test it properly. The oil temperature was by passed.

Tony.

Interesting Tony, thank you. I have never known oil temperature to be taken into account, how should that be done please?

Could it possibly be the reason for the "not OK"?

Ian

 

[t-tony]

There is an oil temperature measuring probe attached to the tester Ian. If you look at the tester screen it will state that oil temperature must always where possible. It may not make enough difference to pass, but the point is you will be testing the engine at a known temperature (80 deg). What it does is alters the parameters for the particular engine being tested.
If you look online for the DVSA In service emissions you will find that your car will be listed somewhere in it.
What a lot of testing stations do is carry out the BET (basic emission test) and if it fails that they call it a fail which they should not do. They SHOULD carry out a full Cat test entering the vehicle particulars and measuring oil temp.

Tony.

 

[Ianmc]

Thanks Tony. The tester has a brand new machine also (installed in the last few days I believe), needed for the new testing regime apparently. Can't help but wonder if there is some operator inexperience with this now. Will get my indy to do the diagnostic thing next week and see where it leads. Really appreciate your input.
Ian

 

[t-tony]

Thanks Tony. The tester has a brand new machine also (installed in the last few days I believe), needed for the new testing regime apparently. Can't help but wonder if there is some operator inexperience with this now. Will get my indy to do the diagnostic thing next week and see where it leads. Really appreciate your input.
Ian

You're welcome mate. Sorry I can't help more.

Tony.

 

[Grumps]

My 2.8 fails on fast idle co2 at a reading of 0.54. Has done for the last 5 years. I may get away with it for one more year as my mot tester is ok about it but he's retiring later this year so I need to get to the bottom of it. I have been advised to change the cat.

 

[Ianmc]

I get the impression that with the new equipment, the MOT tester has little room for "discretion" regarding emissions, in that the results of the analyser are automatically uplifted to the database. Hope my impression is wrong.

 

[t-tony]

The machines do record results to an archive and the station has to keep 3 months of paper copies too.

Tony.

 

[TaffZee]

My MOT due this month Just been looking at its MOT History, cant believe it had advisories when 3 years old..

exempt. Find out more
Date tested 30 May 2017
Pass
Mileage 92,491 miles
MOT test number 2266 0441 3110
Test location unavailable until further notice
Expiry date 29 May 2018
Date tested 13 May 2016
Pass
Mileage 85,412 miles
MOT test number 6742 2513 7711
Test location unavailable until further notice
Expiry date 12 May 2017
Date tested 7 May 2015
Pass
Mileage 76,307 miles
MOT test number 1653 3762 5110
Test location unavailable until further notice
Expiry date 9 May 2016
Advisory notice item(s)

• Offside Rear Tyre worn close to the legal limit (4.1.E.1)
• Nearside Rear Tyre worn close to the legal limit (4.1.E.1)
• Nearside Front Brake hose slightly deteriorated (3.6.B.4d)
• Offside Front Brake hose slightly deteriorated (3.6.B.4d)
• fuel cap sealing washer slightly deteriated

► What are advisories?


Advisory items are provided for advice. For some of these, if they became more serious, your vehicle may no longer be roadworthy and could require immediate attention.

Date tested 2 May 2014
Pass
Mileage 65,627 miles
MOT test number 7899 7232 4106
Test location unavailable until further notice
Expiry date 9 May 2015
Date tested 30 April 2013
Pass
Mileage 54,034 miles
MOT test number 3975 2022 3106
Test location unavailable until further notice
Expiry date 9 May 2014
Advisory notice item(s)

• Offside Front Brake hose slightly deteriorated (3.6.B.4d)
• Nearside Front Brake hose slightly deteriorated (3.6.B.4d)
• Front brake disc worn, pitted or scored, but not seriously weakened (3.5.1i)
• Rear brake disc worn, pitted or scored, but not seriously weakened (3.5.1i)
• Offside Front Tyre worn close to the legal limit (4.1.E.1)

► What are advisories?
Advisory items are provided for advice. For some of these, if they became more serious, your vehicle may no longer be roadworthy and could require immediate attention.

Date tested 30 April 2013
Fail
Mileage 54,033 miles
MOT test number 2089 7032 3433
Test location unavailable until further notice
Reason(s) for failure

• Nearside Front Suspension arm rubber bush deteriorated resulting in excessive movement (2.4.G.2)
• Offside Front Suspension arm rubber bush deteriorated resulting in excessive movement (2.4.G.2)

Advisory notice item(s)

• Offside Front Brake hose slightly deteriorated (3.6.B.4d)
• Nearside Front Brake hose slightly deteriorated (3.6.B.4d)
• Front brake disc worn, pitted or scored, but not seriously weakened (3.5.1i)
• Rear brake disc worn, pitted or scored, but not seriously weakened (3.5.1i)
• Offside Front Tyre worn close to the legal limit (4.1.E.1)

► What are failures and advisories?
Failure items must be fixed before the vehicle can pass its MOT.

Advisory items are provided for advice. For some of these, if they became more serious, your vehicle may no longer be roadworthy and could require immediate attention.

Date tested 24 April 2012
Pass
Mileage 49,319 miles
MOT test number 7485 3521 2159
Test location unavailable until further notice
Expiry date 9 May 2013
Date tested 10 May 2011
Pass
Mileage 42,619 miles
MOT test number 7189 3053 1159
Test location unavailable until further notice
Expiry date 9 May 2012
Date tested 26 March 2010
Pass
Mileage 36,430 miles
MOT test number 5805 2548 0023
Test location unavailable until further notice
Expiry date 25 March 2011
Date tested 25 March 2010
Fail
Mileage 36,419 miles
MOT test number 4337 2418 0000
Test location unavailable until further notice
Reason(s) for failure

• Nearside Rear coil spring fractured (2.4.C.1a)
• Offside Rear coil spring fractured (2.4.C.1a)

► What are failures?
Failure items must be fixed before the vehicle can pass its MOT.

Date tested 12 December 2008
Pass
Mileage 32,691 miles
MOT test number 5511 1734 8326
Test location unavailable until further notice
Expiry date 11 December 2009
Advisory notice item(s)

• Nearside Front suspension has slight movement at a wishbone pin or bush (2.5.A.1c)
• Offside Front suspension has slight movement at a wishbone pin or bush (2.5.A.1c)
• Nearside Front suspension has slight play in a lower suspension ball joint (2.5.B.1a)
• Offside Front suspension has slight play in a lower suspension ball joint (2.5.B.1a)

► What are advisories?
Advisory items are provided for advice. For some of these, if they became more serious, your vehicle may no longer be roadworthy and could require immediate attention.

Date tested 12 December 2008
Fail
Mileage 32,691 miles
MOT test number 6744 8784 8374
Test location unavailable until further notice
Reason(s) for failure

• Nearside Rear Wheel bolt(s) missing (4.2.A.1e)

Advisory notice item(s)

• Nearside Front suspension has slight movement at a wishbone pin or bush (2.5.A.1c)
• Offside Front suspension has slight movement at a wishbone pin or bush (2.5.A.1c)
• Nearside Front suspension has slight play in a lower suspension ball joint (2.5.B.1a)
• Offside Front suspension has slight play in a lower suspension ball joint (2.5.B.1a)

 

[Ianmc]

Wheel bolt(s) missing is not good Lots of suspension wear at 32K miles, car must have been driven hard

 

[littlefeller]

Mine usually fails, emissions. unfortunately it seems a common M44 issue effecting all M44 (just read the posts on any BMW forum).
this doesn't necessarily point to a common factor though.
mine seems to be lambda related, running the car with a duff thermostat may have killed my last cat, now got a cheap one but these don't last.
another option is to put the car through as an M43, ( I didn't just say that, you imagined it, and im not saying I have done this either).
but as Tony has already pointed out - not all stations will actually take oil temp, mine was recorded as normal temp taken from the gauge.
not sure what would happen if for instance there was an oil cooler fitted, surly if you cant get to the correct temp then the emissions test cant be done. @t-tony what happens in this scenario? does it get an automatic emissions pass as its not possible to test it?

 

[t-tony]

Firstly it the car passes the BET test that's it, done.
Only if it doesn't pass the BET test do you have to carry out a full Cat test. The car can only reach its maximum temperature (what ever that is) if it's below 80 reg. it is what it is. No reason not to test the emissions. Car cannot have a Pass if it doesn't pass emissions test first.

Tony.

 

[TaffZee]

Wheel bolt(s) missing is not good Lots of suspension wear at 32K miles, car must have been driven hard

Is there any other way?

 

[Ianmc]

Quick update. Car been to my indy today for investigation of high CO reading at MOT. DME test done, no faults logged in fault memory. Carried out test schedule using diagnostic and information systems including monitoring of status including for air leaks. No air leaks or exhaust leaks found. Found that catalytic converter was smaller than OEM cat. Carried out emissions test to confirm readings of MOT test and to ensure that cat was up to temperature - readings still high.
Car now booked in to have new Powerflow cat fitted next week (had Powerflow boxes replaced last year) to complete (almost) a single Powerflow system. For interest, a new OEM BMW cat is priced over £2K (just silly). Hopefully, the Powerflow cat will be less restrictive and release far greater power!!!!!!!!!
Car is OTR at moment with expired MOT, must get it done earlier next year!

 

[Grumps]

Please keep is informed on this. I have the same problem with mine and it's pointing towards the cat.