DPF replacement

[thomas45]

This is the latest event following on the heels of fuel filter leak.
Now it is the DPF which has been declared beyond cleaning. The car was running well following the fitting of a new fuel filter apart from the odd slight puff of smoke from engine bay. That,I thought, was just the residue of the leak. Two days later however, engine would not start.
Fortunately the car was at home on my driveway and so then recovered to garage for sorting. There was no indication of this problem coming and I ran the car at speed over 40 miles every weekend plus fuel additive every other fill up. (only thing is that I never used Wyns DPF cleaner )
Also I probably should have done more regular oil changes.
This latest event will be expensive and I may consider changing the car for one of those new vehicles of the brand name OX
Thomas

[J44EAG]

Please don`t think me unsympathetic but I`ve little patience with the 2.7D Jaguar power plant.

On paper and in practice, these units appear to be economical and perform well until something goes wrong. Then the trouble can really begin. At the last X350 Seminar, the merits, or not, of the 2.7D were discussed in considerable detail. Delegates attending were shocked by what was revealed. The running costs of the 2.7D when compared to a 3.0 petrol were that you would have achieved a saving of around £1500 running a diesel over the first 50k miles. However, if the diesel then developed faults of the nature you describe, then it was likely that repairs could cost in the region of £4500 to keep the car on the road. A diesel operator would effectively at that point be some £3000 out of pocket. So much for overall economy of running the 2.7D...... The 3.0 petrol car would continue to be reasonably easy and cost effective to run for probably another 30k miles with very little other costs involved until 80k miles were covered. At that point both the 2.7D and the 3.0 petrol cars would be level again and with both probably needing suspension work.

The problem as we are all well aware with the diesels is that they do not respond at all well to short journey use. The resultant effect has cost many, many owners, huge sums of money to rectify. The cars are difficult to home service due to complexity and the need for special servicing equipment. Regular maintenance and even more regular close scrutiny on an almost daily basis is needed just to ensure the car has not gone off tune in some way. Rising oil levels are a typical sign that the car is just about to suffer a mechanical coronary. A new engine block costs just £5000!

I regret to say that I would not touch one of these 2.7D models with a barge pole. They have proved to be a ticking bomb. Defusing it will cost more than half the value of a similar working vehicle. At that point many otherwise half decent cars find themselves in the breakers yard. They were ok one day and dead the next.

No doubt owners who have not had problems will jump to the defence of the model and slam me for saying what I have here. They probably wouldn`t be doing so if their car threw a similar wobbly next week!

It is a shame you have experienced these problems and I hope you can perhaps have a reasonably price fix carried out. Selecting the right man to help you is half the battle. Should you be considering moving away from the Jaguar diesel, then you might consider a petrol engined version in either V6 or V8 guise. These engines have proved to be reliable and do not suffer from the issues that spoil the diesel power unit.

Please let us know how you get on.

Mike K

[robv12]

Got to agree with Mike, 7 turbo's and three engines in on two cars, plus number four gearbox due in one car, nightmare machines, one of mine currently in dock again 700 miles after engine replacement with "restricted performance", looks like a DPF, Diverter valve , or DPF pressure sensor failure already

[thomas45]

Thank you Mike & Rob, I certainly concur with what you both say and now here is my current situation. I have just late today got a call to say car is ready to go, so picking it up tomorrow. I think it is a recon DPF that has been fitted so the cost is not bank- busting. In total 350 dabs ( lost pound sign) . I have been through various issues with this car and at each time they have been sorted it is then brilliant for another while. However, there is always a worry of what may be coming up next.
Yes I do realize I should have got a petrol car in the first instance as not doing enough long runs and eventually I will get one. Just have to wait til the dust settles and the coast is clear ! (if you know what I mean,)
Thomas

[J44EAG]

Short journeys are a diesel killer. If you must do short journeys, they are best followed by a good hard blast of around thirty miles to burn out diesel particulate particles that would otherwise accumulate and block up the DPF once again.

If the car begins a regeneration cycle to self clean the DPF, I strongly advise you to continue to drive the car until the burn out cycle has completed. The burn out adds extra fuel into the DPF units to help a regeneration take place. If the cycle is interrupted by switching off the car, then it will restart from a base point and begin all over again. Repeated interruptions will lead to early DPF blockage and rising oil levels in the engine sump due to fuel wash. This destroys the oil lubrication qualities of the oil which can ruin main bearings and lead to the need for a new engine. In extreme cases, the sump has been known to fill to such a high level that an engine hydraulic lock occurs which bend connecting rods with again a need for a replacement engine. Please check you engine oil levels weekly and note any rise in oil level. Seek professional advice if that occurs.

A stiff maintenance and inspection regime is needed with the 2.7D to avoid cumulative issues. Slow speed driving should be avoided. Diesels need to be pushed quite hard to keep them operating correctly. Soft driving will do more harm than good.

Mike

[jeff1954]

Most of the things that Mike has commented on are correct. However the pre-DPF engine is a very reliable lump As I have said in other sections of our forum I have a pre DPF model It's 12 years old now and has been totally reliable in my 8 years of ownership. I have done all my own servicing once a year 4-5k which is mostly short journey work.

Two years ago I had the cam belt renewed by an independent and that's about it. The car has only done 67k and it runs as sweet as a nut. The point I am trying to make is, that the pre- DPF models are great cars. However this is my first and last diesel engined car as all newer cars whether it's a Jag or BMW ect have the dreaded DPF

As a footnote I have heard of these engines covering huge mileages eg 300.000k and more with just normal servicing.

Jeff

[J44EAG]

Long distance work is what these cars excel. Not so long ago in the X350 magazine pages, we learned of a 2.7D that had covered 407k miles and was still going strong on its original engine. Blasting up and down motorways as a professionally driven company car, it was in its element and was able to regenerate its DPF units without issue.

As previously said, DPF equipped cars when used for short journeys, will usually suffer badly.

Diesel cars nowadays are now almost without exception DPF equipped. That as a long term purchase proposition raises the question of financial viability as a vehicle ages...especially so if the car is used for short journeys. Whilst most of us would go with the idea of good fuel economy from such a vehicle, many people are now considering whether modern diesel ownership is just asking to buy into a pile of trouble for the future. You see few small diesel cars around with the mandatory introduction of DPF forced installation. The small town type cars tend to be petrol powered which is a much better and more reliable option for the sort of use they will be subjected. Namely short journey, local commuter use.

I`ve learned a fair bit about tuning a car for economy, torque, power and drivability in recent months as I`ve rebuilt my petrol 350R. The matter of exhausts and catalytic converter design in ex-factory cars leaves a lot to be desired. Jaguar didn`t help even the XJR when it comes to keeping converter blockages to a minimum level of future potential trouble. The standard 600 cell units can block up very easily even in a petrol car which leads to reduced gas flow, reduced performance and worsening economy as a car ages. New sports 200 cell cats fitted to my own car have a reduced potential blockage area which promotes better gas flow, improved economy (5mpg) and significantly better performance. Yes, such units may cost a little more to fit, but surely that is what should be done to help owners to have to endure less future issues with their cars in the long term. I believe the baton is with manufacturers to put some greater effort into producing higher quality cars fitted at the outset with rather better emission control equipment. DPF filters being a prime example.

I would also suggest that a DPF equipped car would perhaps seriously benefit from a regular DPF deep clean session as commonly carried out by Terraclean. It might reduce the instances of total DPF blockage that we now hear of so regularly.

Mike

[Zennan101]

Hi Mike,
As I have a diesel XF now. I am following this thread with some interest.
A silly question but how are you defining 'short journey' ?
Rod

[J44EAG]

Short journey definition is rather difficult but getting the engine up to operating temperature before any switch off appears to be vitally important so journeys of perhaps only a couple of miles should be avoided. I would have thought anything less than ten miles could also be classed as a short journey.

It is worth mentioning that the effects of a cold start and inevitable excess starting over-fueling are generally said to take at least thirty miles to burn off. Cars used for short journey use will suffer from lubrication oil dilution and contamination and should have their oil change regime carried out at possibly intervals as low as 3k miles.

Mike

[jeff1954]

I've posted this somewhere before. But rather than drive up and down dale in order to get the DPF to regenerate it's self, why not run the engine at fast idle or higher for 20 mins on the driveway. As it's only the engine that needs to be up to normal running temp not the transmission.

Jeff

[J44EAG]

This is probably the worst thing that can happen. Diesel engines need to be run hard under load and got hot.

Sorry, but in my opinion a ten minute run on the drive is likely to do more harm than good. Consider also that for every cold start that occurs, it takes thirty miles of driving to burn out the effects of the start from the engine oil.

Mike