Z4M (E46M3 engine) - Another Lambda Sensor Failure - Grrr!
Discussion
Idle was uneven this morning and at part throttle the engine was hunting but EML light didn't come on. Took it in for diagnostics they said they 'think' its probably the Lambda Sensor aka oxygen or o2 sensor (replaced in May). Seems it had quite a mix of engine control related failure codes. It's covered by warranty but not impressed! Is it a common problem? And if it is why haven't they got them in stock?
Edited by ian in lancs on Wednesday 24th December 09:07
TheEnd said:
it actually said the signal from the lambda is out of the given range.
a hole in the exhaust or an airleak somewhere will also make the lambda out fo range, but that doesn't necessarily mean the sensor is the problem
How do you know what it actually said? Did you do the diagnostics? Could there be an airleak on the intake somewhere - should I look for a displaced pipe? The exhaust doesn't appear or sound like its leaking.a hole in the exhaust or an airleak somewhere will also make the lambda out fo range, but that doesn't necessarily mean the sensor is the problem
The car does a lot of short journeys and doesn't warm up to normal for a few weeks at a time. Then a long run and this problem. I might be drawing a wrong conclusion but the last time the lambda sensor went it was during a long run after a lot of short commutes. Doest the sensor get damaged or contaminated if it doesn't get hot or whatever?
ian in lancs said:
How do you know what it actually said? Did you do the diagnostics? Could there be an airleak on the intake somewhere - should I look for a displaced pipe? The exhaust doesn't appear or sound like its leaking.
It wasn't me, but i do a lot of diagnostics. For a fault to be recognised, an input/output or signal has to be outside of a pre programmed range.
On these narrowband type sensors, they are max and min values, switching times etc, and if these go wrong, it logs an error something like
Lambda sensor - bank 1 - lambda too high
Most garages get as far as the word lambda and just change it, although it often can be a problem elsewhere, and the sensor is just reporting the problem.
For example, if your car stopped, you saw the petrol gauge was at zero, you wouldn't replace the fuel tank sender!
All in all, you need to know what exactly the lambda had a problem with.
The fact you said there was a mix of other codes in there too suggests something else is playing up further up the line
Oh, OK. I understand the principles having designed avionics with built in test and parameter validation software. Problem is I don't get to see the diagnostics screens or study the data so I can't form an opinion. I suppose it depend how sophisticated the system is as to how accurate it is.
ian in lancs said:
The car does a lot of short journeys and doesn't warm up to normal for a few weeks at a time. Then a long run and this problem. I might be drawing a wrong conclusion but the last time the lambda sensor went it was during a long run after a lot of short commutes. Doest the sensor get damaged or contaminated if it doesn't get hot or whatever?
I believe one of the things that contaminates lambda senors is running rich, seeing as most cars run rich whilst the engines cold (Z4M's seem to run very rich during a cold start) it's probably not helping matters. I had the yellow engine warning light come on my Z4M a few months back. They did a reset. It came on again. They said they would replace the lambda sensor. But they don’t keep them in stock. Why do they never keep them in stock! It came on again. So they replaced another sensor. But had to order another one! So, just a faulty sensor & nothing actually wrong with the car. All in all they had the car for a week just to replace a faulty sensor. That they don’t keep in stock. Grrrrrr.
Been having the lambda sensor problems on my M roadster for the last 14 months and in that time they have replaced them 5 times. The last time they even changed the exhaust system and a wiring loom to try and solve the problem. Fingers crossed this has solved the problem.
It seems i do a similar milage to you but this has never been bought up by the dealer as the reason for the failure which suprises me as they have tried most other excuses including contaminated fuel, which was disproved after they removed and drained the fuel tanks.
If you want anymore details as to the repairs that they have done send me a pm.
It seems i do a similar milage to you but this has never been bought up by the dealer as the reason for the failure which suprises me as they have tried most other excuses including contaminated fuel, which was disproved after they removed and drained the fuel tanks.
If you want anymore details as to the repairs that they have done send me a pm.
z4m iain said:
Been having the lambda sensor problems on my M roadster for the last 14 months and in that time they have replaced them 5 times. The last time they even changed the exhaust system and a wiring loom to try and solve the problem. Fingers crossed this has solved the problem.
It seems i do a similar milage to you but this has never been bought up by the dealer as the reason for the failure which suprises me as they have tried most other excuses including contaminated fuel, which was disproved after they removed and drained the fuel tanks.
If you want anymore details as to the repairs that they have done send me a pm.
you have a pmIt seems i do a similar milage to you but this has never been bought up by the dealer as the reason for the failure which suprises me as they have tried most other excuses including contaminated fuel, which was disproved after they removed and drained the fuel tanks.
If you want anymore details as to the repairs that they have done send me a pm.
I drive 3mls e-w to work so for most of the year I don't get the engine warm. It gets a longer run maybe once a week. Th first failure came during an airfield (Prodrive) track day. The second a day after after a 325 mile day long drive. My thought is the low mileage contaminates the sensor followed by a blast tips it over the edge and hello EML goodbye another sensor.
Maybe the use of normal unleaded isn't good for it either?
Problem is apart from having to wait a week to get a new sensor and the car in the same place fixing it is free during the warranty but I can't afford £250+ every six months when it runs out!
Edited by ian in lancs on Monday 15th December 20:35
Top pup said:
ian in lancs said:
The car does a lot of short journeys and doesn't warm up to normal for a few weeks at a time. Then a long run and this problem. I might be drawing a wrong conclusion but the last time the lambda sensor went it was during a long run after a lot of short commutes. Doest the sensor get damaged or contaminated if it doesn't get hot or whatever?
I believe one of the things that contaminates lambda senors is running rich, seeing as most cars run rich whilst the engines cold (Z4M's seem to run very rich during a cold start) it's probably not helping matters. They a little of both really, the engine runs rich, but often there will be a device such as a secondary air pump which puts air into the exhaust, which then is used to burn the spare fuel left over and heat the cat.
From the exhaust, it'd be seen as lean, from the extra air, but the engine has it rich, to compensate for petrol's poorer vapourisation at lower temps.
I hope someone gets to the bottom of this, it is a recurring problem with a number of "guess fixes" which have helped for a while. Swapping the lambda seems to have a good effect, so maybe the lambda is getting damaged, maybe temps are getting too high for them, but the recurring nature does suggest a deeper fault somewhere that is being hidden, not prevented
From the exhaust, it'd be seen as lean, from the extra air, but the engine has it rich, to compensate for petrol's poorer vapourisation at lower temps.
I hope someone gets to the bottom of this, it is a recurring problem with a number of "guess fixes" which have helped for a while. Swapping the lambda seems to have a good effect, so maybe the lambda is getting damaged, maybe temps are getting too high for them, but the recurring nature does suggest a deeper fault somewhere that is being hidden, not prevented
Found this on Tyresmoke - any truth in it? Does running it on 95 ron eventually lead to failure?
"Hi, this happens a lot on german cars which have been run on high octane fuel (shell optimax for example)and then somebody has put 95 ron in it (probably the dealer). The z4M should ideally not be run on 95 ron. If it persists run a few tanks of optimax through it and it will go away hopefully. VW R32s have been known to have this problem"
"Hi, this happens a lot on german cars which have been run on high octane fuel (shell optimax for example)and then somebody has put 95 ron in it (probably the dealer). The z4M should ideally not be run on 95 ron. If it persists run a few tanks of optimax through it and it will go away hopefully. VW R32s have been known to have this problem"
I've had the failure twice - first was faulty wiring connection, second time thing replaced within days.
Problem started on my FIRST TANK OF NORMAL UNLEADED....
But...... I've been running normal now as its so cheap and nothing. Must have been a coincidence
Performance is almost identical too!
Problem started on my FIRST TANK OF NORMAL UNLEADED....
But...... I've been running normal now as its so cheap and nothing. Must have been a coincidence
Performance is almost identical too!Had the two sensors in front of the Cat replaced today.
part numbers...
01 LAMBDA PROBE, BLACK L= 950MM 1 11787540167
02 LAMBDA PROBE, BLACK L= 950MM 1 11787540167
One was showing as 'sensor not connected' (2C3B) the previously replaced as 'open circuit' (2C3D) - last time was 'line fault, open circuit'(2C3C). Looks like they have failed or connector/wiring failure rather than contaminated. In all three cases it states in the report the fault is 'currently not present'.
Technician said they weren't seeing a run on them and mine weren't as contaminated as some he's seen. Shorts runs shouldn't contaminate them although a weekly m-way run would be a good thing to do anyway. He also said choice of fuel shouldn't matter either - SPUL would be better though.
I wonder if the wiring/connector fault is intermittent.
part numbers...
01 LAMBDA PROBE, BLACK L= 950MM 1 11787540167
02 LAMBDA PROBE, BLACK L= 950MM 1 11787540167
One was showing as 'sensor not connected' (2C3B) the previously replaced as 'open circuit' (2C3D) - last time was 'line fault, open circuit'(2C3C). Looks like they have failed or connector/wiring failure rather than contaminated. In all three cases it states in the report the fault is 'currently not present'.
Technician said they weren't seeing a run on them and mine weren't as contaminated as some he's seen. Shorts runs shouldn't contaminate them although a weekly m-way run would be a good thing to do anyway. He also said choice of fuel shouldn't matter either - SPUL would be better though.
I wonder if the wiring/connector fault is intermittent.
Edited by ian in lancs on Wednesday 24th December 09:10
Gassing Station | M Power | Top of Page | What's New | My Stuff