Will do, cat work booked for next Tuesday with MOT retest following.
M.O.T. emissions - FAIL?
- Thread starter t-tony
- Start date
Good news is that had replacement cat installed today, bad news is that car failed MOT for CO emissions again. That said, it was a significantly lower reading with the new cat (around 0.4, had been over 0.5), but clearly not good enough. The tester tried everything for over 20 minutes to get the numbers down and I had run the car for well over an hour to ensure it was fully up to temperature. In the past, could try weakening the mixture at the carburettor, now wondering if "the brain" is at fault. Need to speak with my indy tomorrow, have until Thursday before the retest window expires. Any other thoughts appreciated, could a failing DISA valve cause this?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!
I hope that was copied and pasted and not typed out.....My MOT due this monthJust 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)
► What are advisories?
- 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
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)
► What are advisories?
- 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)
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
Advisory notice item(s)
- 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)
► What are failures and advisories?
- 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)
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
► What are failures?
- Nearside Rear coil spring fractured (2.4.C.1a)
- Offside Rear coil spring fractured (2.4.C.1a)
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)
► What are advisories?
- 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)
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
Advisory notice item(s)
- Nearside Rear Wheel bolt(s) missing (4.2.A.1e)
- 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)
I don't mind any fault except emissions, I can pretty much change the identified part on anything else, but emissions has so many things that could cause the bad results
Bloody hell you got me panicking now! Would a code reader not help identify the problem?Good news is that had replacement cat installed today, bad news is that car failed MOT for CO emissions again. That said, it was a significantly lower reading with the new cat (around 0.4, had been over 0.5), but clearly not good enough. The tester tried everything for over 20 minutes to get the numbers down and I had run the car for well over an hour to ensure it was fully up to temperature. In the past, could try weakening the mixture at the carburettor, now wondering if "the brain" is at fault. Need to speak with my indy tomorrow, have until Thursday before the retest window expires. Any other thoughts appreciated, could a failing DISA valve cause this?
Did they actually measure the oil temp. Ian?
Tony.
Tony.
It had a full diagnostic last week with my indy, no faults stored.
No, but the oil was fully up to temperature, having run the engine at some speed for well over an hour. Would measuring the oil temperature during a test make any difference?
Not yet. Still working on it. So far replaced the spark plugs and air filter. Issue is I have no way of testing it to see if it’s helped unless I put it through the MOT test again, and I can’t do that yet as still have brake pipes and shocks to replace.Did you resolve it @Jjim ?
apparently my M44 smells like an old escort (according to last years tester) it struggled again this year but a new lambda managed to scrape it though.
I went down the same route too - new cat and all that.
@Ianmc does yours suffer from the eratic starting problem?
one thing I have found though is that not all faults are stored, if for instance a sensor is operating inside its designed spec but is close to the edge (like my lambda was) then as it was still in spec there was no error even though it was having an effect, the same happened on my cam sensor too.
I went down the same route too - new cat and all that.
@Ianmc does yours suffer from the eratic starting problem?
one thing I have found though is that not all faults are stored, if for instance a sensor is operating inside its designed spec but is close to the edge (like my lambda was) then as it was still in spec there was no error even though it was having an effect, the same happened on my cam sensor too.
I sat listening to the test while watching the readouts, I did notice there was a just audible miss fire then the readings would rise.
I wouldn't worry too much, think yours is a different problem, if you look through other BMW forums this is a very common trend with the M44, less so with a six pot, the six seems to age really well (unlike the M44) no one really has nailed it down yet.
@littlefeller car starts just fine and runs really well. Did notice a "petrol type" smell from the exhaust which might indicate that it's running rich - not sure what "an old escort" smells like though
smells exactly like you describe@littlefeller car starts just fine and runs really well. Did notice a "petrol type" smell from the exhaust which might indicate that it's running rich - not sure what "an old escort" smells like though
mixed with carbon monoxide.this is the likely cause of the issue.
one other thing I did was to clear memory adaptations.
oops forgot to mention - it was the adaptations for lambda.
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Thanks very much, seems like the next step is to renew the Lamba sensor which, as you say, does adjust the fuelling. Happy days!