Just back from service, all ok. My trusted Indy says the fault code, Permanent DTC P040D. EGR temperature sensor A high circuit, is showing, but does not throw up any dashboard warnings. He says everything is ok, so don’t worry about it. Any thoughts please. 2013 SDV8 4.4 SE Luxor.
1960 Series 2 88 inch diesel.
1955 Series 1 86 inch petrol.

Sorry Guys, did a search and found out what it is. Causing no issues, if it ain't broke, don't fix it. 2013 SDV8 4.4 SE Luxor.
1960 Series 2 88 inch diesel.
1955 Series 1 86 inch petrol.

Do you have a garage at home? Reverse the car in and leave it running, then walk around the back and smell how strong the diesel fumes are... If it stinks like an old ice cream van then go and have the probe changed...

Mine failed and in basic terms, told the ECU the engine was cold! The engine ECU then increases the fuel rate to warm the engine up! All it does then is fill the DPF with unburnt fuel!

Other members have found the probe has failed in a way that doesn't over fuel the car... I'm skeptical the failure must cause some amount of under/over-fueling, however small? And that is a fault that in my book needs to be fixed...

I concur with your thoughts on that, the car will smell less when working properly.

Would this not trigger an emissions test failure. It passed its MOT yesterday. 2013 SDV8 4.4 SE Luxor.
1960 Series 2 88 inch diesel.
1955 Series 1 86 inch petrol.

Not really as it's a temperature probe, I think It's burnt emissions that they are looking for?

But if it’s consequentially over-fuelling / potentially clogging the DPF in some instances, I’d be surprised if the MOT emissions test didn’t pick this up?

It’s also odd to me it doesn’t trigger an EML fault similarly?

NB I also have this error code logged on my L405 but haven’t noticed any overly heavy fumes / smell.

Ok, my thoughts for what they are worth are this… If you have a scale from 1 - 10 and your probe fails in position 1 - 3 for example you may have excessive lean running issues when your engine is cold? And on that same scale 7 - 10 may overfuel? Causing DPF clogging issues?

So, if your car fails on 5 in the above scale and causes you no noticeable issues? Your temperature probe is still not operating within the parameters to heat or cool the engine correctly! Now if you don’t mind risk then this might not worry you? I would prefer to limit the risk and limit the ongoing risk of the probe failing more or in a worse state!?!

There may also be another sliding scale of the degree of failure of the probe? Meaning, if your probe only delivers 80% of its information and in 4 weeks that will decrease to 60% for example? How long before your EML light is illuminated and or your in limp mode?

I like to work on proactive problem solving and preventative maintenance. So I always try to fix these issues as early as I can… 👍

And to add to the above, the cost of a replacement probe & fitting will cost you X at the moment… The cost of the probe PLUS a DPF gets significantly HUGE, very quickly…

Food for thought 👍

It's an easy decision in my book.
Get it changed. It's faulty.
Job done Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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Yep I’d agree - regardless of the fail state / lack of EML, a fault is a fault & the sensor needs changing

There are other larger threads on this subject. On this forum. 2013 SDV8 4.4 SE Luxor.
1960 Series 2 88 inch diesel.
1955 Series 1 86 inch petrol.

Yes, 13 pages of debate  Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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