when i first found out my 2008 (2009 MY) Superb was the PD engine i was worried until i was informed on here that it is a different engine to the "faulty oil pump" PD engines

someone also commented that it was more advanced than the CR engine

can someone please explain in simple terms how the engine is totally different from the other PD engine

and also

how the technology is different/better than the CR as i thought the CR was the latest technology

thanks in advance guys

anybody?

This article from december 1999 explains a little of the differences between CR and PD.

http://www.carkeys.co.uk/features/leap-frogging-common-rail

The oil pump in the MK2 superb is driven using a different method to the troublesome PD140 found in the MK1 Superb.

This article from december 1999 explains a little of the differences between CR and PD.

http://www.carkeys.c...ing-common-rail

The oil pump in the MK2 superb is driven using a different method to the troublesome PD140 found in the MK1 Superb.

so the PD has unit injectors?

i remember one of the tractor units i drove (not sure if it was the Mercedes/Scania/Daf) had unit injectors and i was told they dont have a injector pump because each injector has its own built in? is this correct in my engine?

i have also read on here that the engine is totally different to the MK1 PD engine

how is that so?

sorry about all the questions but i am intrigued

Whoever told you that the PD engine was more advanced that the CR needs slapping around the face with a wet fish!

Whoever told you that the PD engine was more advanced that the CR needs slapping around the face with a wet fish!

http://www.briskoda....p/#entry3012953

post #15

as for slapping with a fish i dont see why?

is it not the whole point of forums to air views and knowledge?

i just want to know a bit about my engine and not get into some arguement.

all i get when i do a search is oil pump problems with the 2.0 ltr PD so wondered how it differs

VAG were really ahead of their game then, the PD was well established even before I was born.

Common rail direct fuel injection is a modern variant of direct fuel injection system for petrol and diesel engines.

On diesel engines, it features a high-pressure (over 1,000 bar or 15,000 psi) fuel rail feeding individual solenoid valves, as opposed to low-pressure fuel pump feeding unit injectors (Pumpe/Düse or pump nozzles). Third-generation common rail diesels now feature piezoelectric injectors for increased precision, with fuel pressures up to 1,800 bar or 26,000 psi.

VAG were really ahead of their game then, the PD was well established even before I was born.

Common rail direct fuel injection is a modern variant of direct fuel injection system for petrol and diesel engines.

On diesel engines, it features a high-pressure (over 1,000 bar or 15,000 psi) fuel rail feeding individual solenoid valves, as opposed to low-pressure fuel pump feeding unit injectors (Pumpe/Düse or pump nozzles). Third-generation common rail diesels now feature piezoelectric injectors for increased precision, with fuel pressures up to 1,800 bar or 26,000 psi.

so are they a kind of unit injector then?

i have also read that the PD engines are easier to remap but have also read they are a nightmare to remap

then there is the people who say a remap is wasted if the DSG is not done at the same time?

there is just way too much info on the net for me and dont know which to believe..............

Direct injection - some clarity in the terms we're using.....

A diesel specialist can correct me if I'm wrong here, but (almost) all modern diesels are direct injection, regardless of whether they are common rail, pump-duse or rotary pump ( GM 2.0 / 2.2 Di < 2005)

Prior to the 1990's, indirect injection was the standard form, but again, this is not so much to do with the injectors, as the way they injected the fuel into the engine. In an indirect engine, the injector sprayed fuel into a swirl chamber - a specific structure in the cylinder head for each cylinder. Here, the fuel and air mixture ignited, with the pressure wave then spreading out through the rest of the combustion chamber.

In direct injection engines, there is no swirl chamber, and instead the cylinder head is almost smooth. Combustion takes place directly within the combustion chamber, often requiring only a slight concave depression in the piston crown. One typical advantage of this is in much shorter pre-heating times. Anyone remember when you had to wait for the glowplug light to go out ? Changed days! Some of the first direct injections were the original VAG TDi, and the Perkins Prima found in BL Maestro and Montegos

In a PD engine, the camshaft bears down on the injector, creating the high pressure required for efficient fuel atomisation and combustion. In later PD engines, the injector is opened and closed by a piezo crystal, driven from an ECU.

In common rail engines, the injector has no pump function. The car is fitted with a high pressure fuel pump, supplying a constant supply of highly pressurised fuel at each injector. The injectors then open and close (again using a piezo crystal, and under the control of an ECU.

So - to sum up. Almost all modern diesels are direct injection, and indeed, have their injection controlled electronically through piezo crystals. In common rail, one pump delivers very high pressure fuel to all injectors all the time. In a PD engine, the fuel arriving at the injector is at lower pressure, but the action of the camshaft on the injector raises the fuel pressure (hence the 'pump' in 'pump duse')

thanks for the replies folks

im very interested in knowing what is the mechanical difference of the PD engines between the mk1 & mk2 Superb

i now know my engine does not suffer with the oil pump issue but dont understand how it is a totally different engine?

as for the CR & PD debate it depends who you ask and what their personal view is as to what people think is the better engine

i have a friend who is a diesel specialist and he says the CR is the better engine but his partner prefers the PD engine and thinks although its noisier it is a better engine

A very good explanation of the differences in injection systems in my opinion.

Indirect injection used to be used on cars, because direct injection used to give a very noisy engine we all know and hate. Then a few systems came along which allowed direct injection to be more controlled and therefore less rattly. This was achieved in different ways, some still using mechanical injection but maybe with dual rate springs in the injectors. Others used unit injectors (PD stand for pump duese, badly translated to unit injector) or full electronic control of the injectors by common rail. I think the first production car engine with common rail was the Rover 75s diesel engine. I seem to remember the BMW version of the M47 didn't use CR but maybe wrong.

High pressures are needed in order to get the diesel into the combustion chamber. Much higher than in a petrol car where the fuel is injected into the manifold. In a conventional diesel engine theres an injection pump that provides this pressure, and controls the amount of fuel. You can control this pump electronically and many none PD engines use this including VW.

With a PD engine there's no central pump, as described above the pressure is provided by each separate injector being pushed by the camshaft. A little valve controlled by the ECU controls the fuel by releasing the pressure when injection is finished. I don't think any use the piezo alone to provide the pressure, only to control it.

Common rail is much more like a petrol injection system although at much higher pressure. Again as described above a mechanical pressure pump feeds fuel to the injectors, and the ECU can control the pressure in this feed pipe (the common rail), too. Then each injector is opened by the ECU,to inject the fuel. These injectors can be either electromagnetic (early) or piezo (newer) controlled.