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With your pattern of useage you shouldn't be getting amber DPF warnings let alone red one. My driving pattern is similar to yours & I've never seen a DPF warning in over 200,000 miles.

The problem is either one of the differential pressure sensors or there's an underlying problem that's preventing the engine running in the emissions sweet spot. A leaking intercooler flange on mine reduced the regeneration cycle from 1000-1200 miles down to a couple of hundred miles or less. That gives some indication of how much more soot is produced by poor combustion.
stig; How did you discover the leaking flange ( smoke/hand?) mine is doing 200 miles regens despite mwah at 65-70 and a few hillclimbs in Cornwall on the a30. Regens are about 10 minute at a time bu5 the in between mileage seems a bit short. Mpg is 50+ in this weather.
 

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Similar problem to the OP. 3.0 diesel XF. Thanks for the help in this post. I rang the warranty people who told me to call out the Jaguar assistance.

Apparently there is a bit of a fault with the flap on the throttle body. It sticks and the air is drawn in via the EGR filling the DPF quickly. He replaced the throttle body, checked the software (it was up to date) and then we went for a run and he checked again. Soot down from 26 grams to 5 grams. Sorted.

Well impressed with Jaguar warranty and Jaguar assistance.
Does anybody know if this would cause a problem with regens? As some of you know, the issue I have is that a regen won't drop the soot level below 20 grams but we don't know why. Everything else we can think of is as it should be, no leaks, nothing.
 

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Some snippets from the workshop manual if it helps for more ideas:


During the active regeneration process the following ECM controlled events occur:
  • The turbocharger is adjusted to reduce boost pressure. This minimizes heat transmission from the exhaust gas to the turbocharger and reduces the rate of exhaust gas flow allowing optimum heating of the DPF. If the driver demands an increase in engine torque, the turbocharger will respond by closing the vanes as necessary
  • The intake throttle is adjusted as this assists in increasing the exhaust gas temperature and reduces the rate of exhaust gas flow which has the effect of reducing the time for the DPF to reach the optimum temperature
  • The EGR (exhaust gas recirculation) valve is closed. The use of EGR decreases the exhaust gas temperature and therefore prevents the optimum DPF temperature being achieved.

During active regeneration, the EGR operation is disabled and the closed-loop activation of the turbocharger boost controller is calculated. The air management module controls the air in the intake manifold to a predetermined level of pressure and temperature. This control is required to achieve the correct in-cylinder conditions for stable and robust combustion of the post injected fuel.

The module controls the intake air temperature by actuating the EGR throttle and by adjustment of the turbocharger boost
pressure control.

When the supervisor module issues a regeneration request, the co-ordinator module requests EGR cut-off and a regeneration specific turbocharger boost pressure control. It then waits for a feedback signal from the EGR system confirming that the EGR valve is closed.

When the EGR valve is closed, the co-ordinator module initiates requests to increase engine load by controlling the intake air temperature and pressure.
 

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Much appreciated, but I've read the workshop manual notes until I'm blue in the face. Anyway, the compressor actuator is being changed tomorrow so hopefully that might solve the RP issue but I doubt that's causing the regen problem. They're going to remove and check the EGR valves at the same time.

I'm going to try a different approach and do a diag with the Autel kit when it comes back, and see if anybody else can do a similar one so I can compare data. If we find something that's different, it may point to whatever is causing the problem.
 
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