Hi, having posted a few times about an issue with oil dilution, I bit the bullet and bought a GAP IID diagnostic tool to get some live data and also had the fuel pump rebuilt and leak checked.

It awaits to be seen whether the pump was the main cause of the oil dilution (unfortunately the place I took it to didn't do a pre-test on it to see if it was leaking before rebuilding it ). I'll monitor it over the next 1k miles or so.

Having now got the diagnostic tool though I was able to log some interesting data on a long journey this weekend and wanted to check some points out... The following was logged over a 3hr10min drive covering ~130miles. Parameters are simply soot mass as inferred from the differential pressure sensor and number of demanded DPF regens;

Click image to enlarge

A simple boost leak can cause too much soot, as can a leaky injector as can a restricted air intake as so could a problematic EGR valve. Jaguar x-type sport gone
Jaguar x-type 2.2d sport one of my best cars ever sadly gone
Freelander 2 GS auto 2008 most unreliable ever ! gladly gone
Freelander 2 GS manual 2013 only time will tell !

What Engine oil are you using

Have you checked the DPF pressure sensor, the two hoses are known to fail

oldgeezer wrote:

A simple boost leak can cause too much soot, as can a leaky injector as can a restricted air intake as so could a problematic EGR valve.

I Like Chips wrote:

Have you checked the DPF pressure sensor, the two hoses are known to fail

Here is a movie on the sensor. check the pipes, maybe get them off and check for splits

freypal wrote:

I Like Chips wrote:

Have you checked the DPF pressure sensor, the two hoses are known to fail

Also on the sensor does anyone know what the pressure value should read with the ignition on, engine not running. I would have assumed it would be 0kPa given there is no exhaust flow across the filter but mine reads 1.0kPa on the IID tool. Not sure if there is a permanent offset applied?

I Like Chips wrote:

Here is a movie on the sensor. check the pipes, maybe get them off and check for splits

JonMs wrote:

freypal wrote:

I Like Chips wrote:

Have you checked the DPF pressure sensor, the two hoses are known to fail

Also on the sensor does anyone know what the pressure value should read with the ignition on, engine not running. I would have assumed it would be 0kPa given there is no exhaust flow across the filter but mine reads 1.0kPa on the IID tool. Not sure if there is a permanent offset applied?

I've just gone out and checked, ignition on, engine off, GAP IID BT gives a value of 1.0kPa for DPF pressure on my 2011 SD4. Same as your value. Also, have you seen this video? it might be useful.

Had a quick look at the throttle body flexi hose which normally seems to go and can't see any obvious splits in it. Flexi hoses attaching to the DPF pressure sensor also look good....

Are there any possible/likely things to look for which could cause excessive soot generation but also wouldn't manifest as reduced performance or log additional fault codes? Seems odd the car runs fine with plenty of power etc.

Just to say, in addition to the DPS sensor pipes splitting etc, the DPF sensor itself can fail. Mine failed just after I bought the car and was difficult to diagnose. The only symptoms were the car going into Reduced Performance mode intermittently . There were no fault codes. It was fixed under warranty so unfortunately I don't know exactly how the mechanic diagnosed the problem, only that he used live data and the voltages were out.

JonMs wrote:

freypal wrote:

I Like Chips wrote:

Have you checked the DPF pressure sensor, the two hoses are known to fail

Also on the sensor does anyone know what the pressure value should read with the ignition on, engine not running. I would have assumed it would be 0kPa given there is no exhaust flow across the filter but mine reads 1.0kPa on the IID tool. Not sure if there is a permanent offset applied?

I've just gone out and checked, ignition on, engine off, GAP IID BT gives a value of 1.0kPa for DPF pressure on my 2011 SD4. Same as your value. Also, have you seen this video? it might be useful.

Hi again, sorry but in relation to your latest reply on faulty pressure sensor...

Could I possibly trouble you for another check when you have time? With the ignition on and the engine off, is your pressure sensor voltage signal steady? I'd assume it should be rock steady as there is no exhaust flow so no possible change in pressure. Mine is jumping between two values though. I know they are very small changes but I wonder if it indicates the sensor might be having problems...;

Click image to enlarge

With the engine idling the value seems to oscillate a lot more but i could probably believe that. although it would be interesting to see if it's normal! The youtube videos you kindly linked seem to show a much more stable value than i have too...;

Click image to enlarge

On my car the values with ignition on but engine off are very similar to your graph in that the voltage oscillates between two values and is very stable. The only difference is that my values are higher, between 0.493 and 0.498. I don't know if this is significant or not.

At idle my graph is similar to yours in that there is much more variability in the values. They range from 0.488 to 0.547

I'm not sure if this helps you or not! my gut feel is that your DPF sensor is fine because it's behavior is similar to mine. The values may be slightly different but then my DPF is likely to me more or less full than yours.

Hi having read the above I would ask the following basic questions in order to try and understand the basic issue.

* Have you owned the vehicle from new if not how long
* Current mileage
* Full service history with LR dealer or Independent garage
* Type of engine oil used (should be C1 5w-30 spec such as Castrol Edge Professional, and must meet Ford WSS-M2C934-B, ACEA C1 and latest spec ST JLR 03.5005) these are low ash engine oils that are required for the Freelander 2 not a generic one that most non franchised garages might use.
* Has the engine been remapped or the EGR blanked etc;
* How is the vehicle driven, Motorway, Rural, Urban and average journey time and number of miles covered.
* Average road speed/engine RPM
* Do you use the vehicle for towing.