Hmm I guess I will have to treat my unmodified 130?with kid gloves and think about an oil change every 5k in that case.

Hmm I guess I will have to treat my unmodified 130?with kid gloves and think about an oil change every 5k in that case.

My old 2003 PD130 i sold last year has now over 200,000 miles and most of that was producing 220bhp. The engine is still perfect and still makes the 220bhp on a RR with that mileage, everything original on engine(injectors etc). Before i sold it i inspected the camshaft and was in perfect condition.

Most of it's life it was using longlife oil and i used to change it between 8-10k.

Rotodiesel, what mileage are you seeing the 130 worn out at? Piston wear etc?

A very interesting read lummox and rotodiesel...i get the impression that the pump duse technology although maybe outdated in terms of the new common rail diesel models for sale in the showrooms now, and the older version (pd) engine being phased out in the near future. I myself would feel happier that the fuel pump on the pd engine is imersed in oil and very well lubricated, compared to the common rail pump being fuel lubricated...it will be interesting as the months go by and god forbid new owners reporting pump problems on their common rail engines.

I would sooner shell out for a new particulate filter on the pump duse superb which is a lot easier to replace than strip the front engine to gain access on the common rail engine to replace the pump and possible fuel lines, as i believe they are sold as a complete item.

So although the older / newer superb models have the 140bhp pump duse engine, the newer 140bhp superb engine is still a good buy and should provide more reliable ownership, while its stablemate the 170bhp common rail brother might be experiencing problem later in its life through lack of lubrication to the pump.Sounds like its the cars coronary (fuel pump) that could be more expensive to fix than the particulate filter on either the older 140 facelift superb or the superb mk2.

Outstanding thread this. Thanks to all the expert contributors.

Just a layman's observation, I suppose a PD car that has been mildly driven would exert less stress on its top end, since mostly, the solenoid valves on the pump injector are open, spilling fuel back into the return line rather than forcing it through the nozzel and therefore not hammering the camshaft and rocker roller. If it is a high power model that has been driven hard, the pump injectors will have been putting much more force on the cam shaft and rocker - I suppose.

Anyway - great thread.

Edited 3 April, 201016 yr by EvilV

Just to add a little more back ground information.

Common rail is not a new idea, it has been used in Marine Diesels for a long time.

Old British built Doxford Diesel Engines utilized common rail fuel injection in the thirties right up to the eighties.

Strange thing is that individual injection system(PD) eventually became the industry standard but now Marine diesels are returning to common rail.

Looks like its turning full circle.

I have just ordered a Octavia Scout 2.0 CR and I must admit I am slightly apprehensive considering just how reliable the PD engines have proven to be.

Only time will tell.

A few people have asked me so i thought i would try to explain.

Around the year 2001 VW/Audi introduced the PD engine. Not a new design in theory as this type of diesel injection had been used for many years in marine applications but it hadn't come this far in terms of control. A unit injector is fitted per cylinder. The injector includes its very own high pressure pump (internal pressures of 2050 bar on the 1.9 and 2200 on the later 2.0 piezo injectors). The injector and the pump is run off the camshaft, with a cam lobe pushing down and generating the pressure. The solenoid controls the amount of fuel that is required, timing if the injector is mechanical still.

This is the fundamental problem with the PD engine and what will eventually lead to its sad demise. With new legislation all diesel engines will need to run a DPF to meet Euro 5 regs (IIRC). To activate self regeneration, a very late cycle of injection needs to be added; the fuel is injected post combustion which increases exhaust temperature which starts the regeneration process. As the timing of this injection is controlled by a mechanical factor, i.e the camshaft, there is only so much that can be done. The PD engines fitted with the DPF have a different camshaft with an additional profile to the lobe; this gives another fuel injection post combustion for regeneration. However this all has to happen within 360 degrees of camshaft rotation. For there to be time for the injector to work again for the next cycle, this obviously has some serious limitations.

With the advent of 'us' using a CR system, fuel pressure is supplied by a very high pressure pump (circa 180bar, so don't go cracking any pipes off!) to a manifold (or fuel rail) that then supplies the injectors. The injectors are then controlled by the ECU. The injector can then be mapped to deliver whenever it is required giving a greater level of control. This is also why they have been able to drop the compression ratio and make the engine quieter in operation.

I hope you find this information interesting if not usefull. Its all off the top of my head so feel free to take it with a pinch of salt

Very good, well explained

Hi that was and is a great debate !

just thought i would put my pennies worth in i have a 16 year old Mitsubishi Delica 2.8 td that uses a mechanical pump and egr valve and one of the first things you do to enable it to pass uk emmisions for the MOT is block up the egr with a blanking plate, also one of the common problems that effects these engines is the faliure of the fuel pump seals allowing fuel in to the sump this is due to the seals perashing due to the ultra low sulphor fuel we now use in the uk, and its a pig to change the £2.00 seal 6 hours in and out !

the down side of this is that if left then the oil and fuel i belive get past the rings and the engine will burn itself out until it goes bang !

so whats the chances of this occuring with a CR engine

Andy

Well there's nothing wrong with the original article (not surprising given its source), but the obsession with diesel particulates is nonsense.

The Germans did some experiments on the subject in the 1980s, and found that half of all PC-10s at that time were from tyres and brakes. Since then, ULSD alone has more than halfed PC10s from diesel exhaust, and higher combustion temperatures have halfed that again. So, assuming the same breakdown of traffic by engine type and total fuel mileage (percentages), only 1/8 of PC10s are diesel exhaust anyway at Euro3. Why chase an already low and decreasing fraction of the total?

If I could chip in here with my two peneth.

I have owned a VW Passat PD, I got it from new and it covered 140,000 miles in three years, oil was changed every 20,000 miles or as indicated by the long life service and I drove it hard most of the time, also towing heavy loads, it would burn 1 litre of oil every 7 thousand miles and I used 5/30 synthetic oil. This car did not ever let me down, fuel economy was always high 40's and got better as it got older.

I now drive an Audi A4 B8 CR TDi, I have had this car for 2 and a half years, it has covered 110,000 miles and has had the same long life servicing as the VW did, the CR engine does not use any oil between servicing. The fuel economy is worse than the PD and it is not as free revving as the PD either. When driving and the DPF decides a re gen is needed this is also noticeable as it ticks over at 1,000 rpm and is much more responsive when driving. Having said this though I have also worked the Audi hard and it is still as good now as when I got it.

I am looking forward to the delivery of a 170 TDi Yeti, let's see how that fairs when it too will clock up 140,000 miles over three years

Very informative thread, Thanks

My 2006 VW Jetta TDI has a PD motor. When I first got the car new in 2006, the 505.01 oil available at the dealer was 5W40, but soon after the dealer only offered the 505.01 in 5W30. Being suspect of the trend toward thinner viscosities, I found a source of 505.01 5W40. I have had an incidence of failure of the cam and/or cam follower around 245,000. I have faithfully changed the oil and filter every 5000 miles always using the same oil spec and viscosity.

 

After reading your forum and the comments about the top end lubrication challenges, I am wondering if my choice of viscosity is still the best decision? I would appreciate your advice.

Another key advantage of the Common Rail over PD is the effects of presurised vs unpresurised volumes.

 

With a PD system the solenoid actuator is in line with the pumping element and acts as a diverter valve - The fuel is either directed to the nozzle for injection or dumped back to tank. This has the effect that once the injector starts the injection cycle the all of the fuel down stream of the actuator has to be pressurised before injection can start and the that pressure decays gradually over time once the actuator stops the injection. The net effect is that the actual injection pressure is low as the start of the injection stroke and so not as well atomised as in mid-injection. This reduces power and increases NOx / SOx / particulates due to inefficient combustion.

 

With a CR system the "rail" acts as a pressure vessel at higher pressure than PD can generate. The control of the injection is very close to the nozzle as so there is a much reduced time lag between the actuator opening and the injection starting / stopping and also a higher and more consistent injection pressure so better power delivery and emissions control through cleaner combustion. Another advantage of the more rapid response and constant supply of pressure is the ability to do pre-injection and other injection timing tricks (sometimes linked to water injection of bigger engines).

 

The key down side of CR is the increased complexity of the pump and injectors, especially around materials and manufacturing technologies.