Nearly two years into my 4.4 tdv8 (Westminster) ownership.

Love the car but I never fully realized the pain these DPF''s cause.

I've had the amber light on maybe 8 times in 20 months. Lately it has even been coming on after a long motorway stint with a short journey the next day. There is obv a problem that needs resolving. I plan on going to see the DPF Doctor this month to get to the cause of this. Has anyone used DPF Doctor on here?

Given DPF doctor sells DPF cleaning, that's all they'd probably recommend. The DPF filling is a symptom on these cars, so I'd be highly doubtful a clean would ever cure the problem and it would just return, meaning wasted money.

There's a few common causes on the 4.4 TDV8, all of which are relatively inexpensive fixes:

A thorough inspection of the 4 hoses on the "donut"/air intake manifold, plus the 2x charged air hoses at the front of the engine bay is a must. As you face the engine bay, the charge hose on your right hand side heads into a metal union which joins the throttle body. Inside this union is an o-ring which collapses over time - there are some interim fixes possible, however will eventually require the whole part replacing. Here's the links:

https://www.fullfatrr.com/forum/topic55270-30.html
https://www.fullfatrr.com/forum/topic65810.html
https://www.fullfatrr.com/forum/topic64236.html
https://www.fullfatrr.com/forum/topic64236-45.html

Usual causes are:

1. Sooted up MAP sensor, which should be cleaned every few thousand miles. This is free so, try it first. Remove the engine cover and it's pretty obvious - has 1x T20 screw on it and a multiplug going to it
2. Have a good look at and around the 4x hoses on the 'donut' (inlet manifold) plus the two top charge hoses (the big rubber hoses at the front of the engine bay). Look for soot or oily deposits in their vicinity or white gunk
3. Failure of the seal inside the union between the throttle body and top left hose (a very common failure). This can be bodged with gas specification PTFE tape or the part needs replacing (£175 but takes 5 minutes to fit on the driveway with no more than a screwdriver). Look at the top left hose adjacent to the left airbox and follow it until you see a plastic fitting with a metal clip. It usually fails in this area so, you'd see sooty deposits around the fitting and on engine components nearby
4. Exhaust Gas temperature sensors down the sides of the EGR on the exhaust manifolds. P040D is a known error code of the sensor failing on the nearside exhaust manifold down the side of the engine.

Less common culprits are the temperature sensors beyond the exhaust manifolds.


If you're Southampton way, I don't mind running my IID tool on your vehicle and picking up any error codes to confirm anything else. 2015 Range Rover Autobiography 4.4 SDV8

What Gary said. You have a leak in your pipes or maybe a prob with your sensors or even your thermostat/housing (mine was damaged during a repair and made the engine run too cold to regen fully).

the DPF prob is a symptom and not a cause. get a HIGH pressure smoke test done asap cheapish and good for fault spotting.

Thanks for the reply. No doubt you are right. Its a bit odd as the Indy that I use said no air leaks and sensors were all ok when I was there so Im guessing what the cause could be.

Regarding the Dpf doctor, when I spoke to them they did say that they won't do a clean until they've sourced the route of the problem unlike most dpf clean companies who just clean and ignore the cause.

Ill try the things you have mentioned but if this keeps happening I'll visit the dpf doc.

Have you had a HIGH pressure smoke test done? bear in mind my inlet manifold crack was very small and only just perceivable with a smoke test but had a huge effect on the DPF.

Agree with other comments, there is clearly something amiss here. Being gluttons for punishment we have two L322 TdV8 4.4's, one does mainly short journeys (less than ten miles generally) and the other does mainly long motorway journeys. We've owned both for over three years and neither has ever had even a DPF warning light, let alone an actual problem. Always change oil regularly every 7500 miles max and always use correct grade premium product (usually Shell Helix) and never use supermarket fuel (generally it's Shell from the local fuel station, but always premium), I have no idea if this is a factor but compared to what others seem to be getting DPF trouble wise I reckon this is actually the cheaper option. Drives:
2010 FFRR TdV8 Vogue - Stornoway Grey
2010 FFRR TdV8 Vogue SE - Zermatt Silver
1998 BMW E36 M3 GTII

Glenney, yes I have used DPF Doctor through one of their franchise sites in Newbury at Millers Garage. I would recommend. They do know what they are talking about and, as others say, your DPF is the symptom and not the cause. Their USP is not simply cleaning DPFs - it is an holistic approach to the whole system and they are well aware of the impact of intake-side leaks etc on soot build up. When and only when they have identified why your DPF is not operating as intended, they will chat to you about options going forward. As long as the DPF is not damaged, they will be able to clean it which will give you an ‘almost new’ DPF. However, it is very important to diagnose the cause of the problem. Good luck! 👍 Andy

2010 4.4TDV8 Vogue SE in Santorini Black with Ivory interior
2017 Audi SQ5 3.0 V6T Quattro in Volcano Red
2001 Audi Allroad 2.5 TDI manual with low-range in Highland Green. Currently SORN whilst undergoing some serious restoration!

I second that approach sir... Needs diagnosing properly...

Have a read here:
https://www.ctscorp.com/products/sensors-2...operation/

As far as I understand every diesel engine produces soot, no way around it.
A new diesel engine, using the highest quality fuel and oil, cleanest air filter, you name it, will produce soot.
Soot is burned into ash by regeneration (passive or active) and the ash stays in the dpf.
The only way to remove the ash is using another process.

Cleaning a dpf is IMO part of owning a diesel engine.
How often this needs to be done has many parameters.
But at some point it's necessary.
By my calculations, cleaning the pdf pays for itself after 40.000 /50.000 km.
It does so by reduced regeneration (= burning extra fuel) and less overall fuel consumption.

 2012 4.4TDV8
2000 Honda S2000

DPF's are designed to last way longer than that before ash buildup becomes a problem. The extra fuel used during regeneration is insignificant. 2012 TDV8 Vogue (L322)