Exhaust Sensor Light /NCT

guido

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Hi

Looking for some advice please - I have a mini one 2015 diesel - approx 80k km
My car has an orange engine light on - more on than off. A mechanic has swapped the exhaust sensor as this was the error showing but the light is still showing

My first question is - I have the NCT next month. Will the car be disqualified for testing due to the light being on?

Secondly - any advice going forward. The mechanic is now recommending a DPF? Believe 300-500 euro?

Or do you think at this stage I should go back to a mini garage for a diagnostic check - approx 130 Euro to check that the DPF is the right way forward?

Anyone else experience these same problems?

Any help greatly appreciated - thanks
 
The National Car Test (NCT) Manual documents all the tests performed.

Section 60 (page 103) covers the malfunctioning indicator checks and the engine light is not one of them. Nonetheless you ought to have it checked out because there may well be an underlying problem which could result in a failed test.

So first things first, get the diagnostic check done and take it from there once you know what the issue is.
 
Before you spend any money, Take it for a long run 40-50 Kms, motorway is ideal, keep the engine at say 3000 rpm in 4th or 3rd as steady on the pedal as you can, hold the speed for 15-20 Kms or so, this should cause the system to regenerate and might just might clear your dpf which may indeed be clogged, if this fails ask your mechanic about dipenthane which might be beneficial and after adding it do the above again.

Do you have the opportunity to drive distances often or is it mainly short journeys.
 
The National Car Test (NCT) Manual documents all the tests performed.

Section 60 (page 103) covers the malfunctioning indicator checks and the engine light is not one of them. Nonetheless you ought to have it checked out because there may well be an underlying problem which could result in a failed test.

So first things first, get the diagnostic check done and take it from there once you know what the issue is.
Thanks Andrew. I looked at an NCT doc this morning and it said if the engine light is showing for a diesel car, it will be rejected for a smoke test? Not overly familiar myself but don’t want to waste money if it will just be rejected immediately - thanks again
 
Before you spend any money, Take it for a long run 40-50 Kms, motorway is ideal, keep the engine at say 3000 rpm in 4th or 3rd as steady on the pedal as you can, hold the speed for 15-20 Kms or so, this should cause the system to regenerate and might just might clear your dpf which may indeed be clogged, if this fails ask your mechanic about dipenthane which might be beneficial and after adding it do the above again.

Do you have the opportunity to drive distances often or is it mainly short journeys.
Thanks Palerider - yes it’s generally short journeys alright - my mechanic has suggested driving it “harder” - and I took it on the motorway in 4th gear and did as he suggested - the same as you - but not for the distance that you are suggesting - I might try that then - also the light is generally on but goes off intermittently for approx 100 km - I see a company on line that dies dpf cleaning - 200 euro based in airside - might have to take that route - thanks for the response - much appreciated
 
You can get it cleaned but try my suggestions first, short runs are your problem, very common issue, diesel cars should be used by people who make longer runs at least weekly, I'm a low mileage diesel driver but have long country runs at least fortnight, I never had an issue and I occasionally drive for periods at higher revs lower gears to ensure system is whistle clean, you may have to do as suggested a few times and factor in a long journey if you find it helps.
 
You can get it cleaned but try my suggestions first, short runs are your problem, very common issue, diesel cars should be used by people who make longer runs at least weekly, I'm a low mileage diesel driver but have long country runs at least fortnight, I never had an issue and I occasionally drive for periods at higher revs lower gears to ensure system is whistle clean, you may have to do as suggested a few times and factor in a long journey if you find it helps.
Many thanks - appreciate that
 
Dipetane, €10 or so from any motor factors, added to the fuel tank in the correct proportions and a 20/25 mile spin at motorway speeds with the engine up to temp should clear simple problems. If the light persists, see a good diesel mechanic.
 
Dipetane, €10 or so from any motor factors, added to the fuel tank in the correct proportions and a 20/25 mile spin at motorway speeds with the engine up to temp should clear simple problems. If the light persists, see a good diesel mechanic.
Thanks for that - I tried a spin on the motorway tonight - no change unfortunately
Haven’t tried the Dipetane option yet - so that’s the next move - thanks for your help Mathepac
 
Can you take a picture of the dash with the light on and post it here, just to be sure.
 
Hi Mathepac
I can but the light is the engine light - The mini one d does not have a specific dpf light - the error when checked refers to the exhaust sensor and that has been replaced so my mechanic believes now that the error is coming from the dpf - thanks for the follow up - let me know what you think - thanks
 
Before you spend any money, Take it for a long run 40-50 Kms, motorway is ideal, keep the engine at say 3000 rpm in 4th or 3rd as steady on the pedal as you can, hold the speed for 15-20 Kms or so, this should cause the system to regenerate and might just might clear your dpf which may indeed be clogged, if this fails ask your mechanic about dipenthane which might be beneficial and after adding it do the above again.

Do you have the opportunity to drive distances often or is it mainly short journeys.
Excuse my ignorance, but how do you do this on an automatic?
 
Hi Mathepac
I can but the light is the engine light - The mini one d does not have a specific dpf light - the error when checked refers to the exhaust sensor and that has been replaced so my mechanic believes now that the error is coming from the dpf D2C6827F-DA1F-42B0-87FE-42CAD7D93A26.jpeg
 
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Just to mention too that I am seeing no performance issue - or extra fuel being required - thanks again
 
That light is commonly referred to as the “check engine light" or CEL. It and other warning lights come on as part of the ignition cycle. Lights that stay on after the engine has started, like on your car, need diagnosing.

If your mechanic has run his computer diagnostics and replaced a part but the light persists, then he hasn't sorted out the problem. There is more than one exhaust sensor in a modern diesel car and there may be more than one problem. I think he needs to finish what he started and not keep stabbing randomly about in the dark.

Try my suggestion and if it doesn't eliminate the problem, go back to the mechanic.

Just as a matter of interest, was the diesel car the sales person's idea of your perfect car or yours? There are plenty of examples of sellers foisting diesel onto unsuspecting customers where their regular usage would indicate that petrol or even electric was the more appropriate option.

A Hyundai sales creep tried to sell my sister one last year until I stepped in and he scuttled off.
 
That light is commonly referred to as the “check engine light" or CEL. It and other warning lights come on as part of the ignition cycle. Lights that stay on after the engine has started, like on your car, need diagnosing.

If your mechanic has run his computer diagnostics and replaced a part but the light persists, then he hasn't sorted out the problem. There is more than one exhaust sensor in a modern diesel car and there may be more than one problem. I think he needs to finish what he started and not keep stabbing randomly about in the dark.

Try my suggestion and if it doesn't eliminate the problem, go back to the mechanic.

Just as a matter of interest, was the diesel car the sales person's idea of your perfect car or yours? There are plenty of examples of sellers foisting diesel onto unsuspecting customers where their regular usage would indicate that petrol or even electric was the more appropriate option.

A Hyundai sales creep tried to sell my sister one last year until I stepped in and he scuttled off.
Thanks again - the good news is (and I hope that this isn’t short lived) the light has gone off again! I bought dipetane at lunchtime - added the correct amount and took the car for a short drive on the motorway- nothing immediate- then after work when I switched the ignition on, the light didn’t remain on - hopefully something positive now. No, I can’t blame the sales guy - was doing more mileage for work at the time and actually traded in a petrol. And yes, not impressed with the mechanic as I’ve been left in the lurch - hopefully the dipetane will sort it for good - only time will tell - thanks again
 
You're welcome. On an on-going basis, top-up the dipetane as you refill the tank, using the guide on the side of the bottle for dosage, just make note of the litres you buy.

I'm a committed dipetane user since switching to diesel a few years ago. Amongst other benefits, it helps compensate for bad/dirty fuel. Don't let your tank run down too low, change the fuel filter as often as BMW recommends, same with the air-filter, both are DIY jobs.

Happy dieseling!
 
You're welcome. On an on-going basis, top-up the dipetane as you refill the tank, using the guide on the side of the bottle for dosage, just make note of the litres you buy.

I'm a committed dipetane user since switching to diesel a few years ago. Amongst other benefits, it helps compensate for bad/dirty fuel. Don't let your tank run down too low, change the fuel filter as often as BMW recommends, same with the air-filter, both are DIY jobs.

Happy dieseling!
☹️ Light just came back on - I’ll bear with it for a day or so and see if it goes off again - thanks for the advice
 
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