Pump Duese 101

[Turbo Steve]

Simplified Version of Pumpe Duese 101

To simplify things for our valuable newer members of Fred's good Forum, the Pumpe Duese (PD) Injection System is just another way to increase injection pressure to the TDI's fuel injectors in order to vaporize and atomize the diesel fuel spray more effectively. (Note - Current TDI Injection Pumps already produce about 16,000 PSI with the 10mm injection pumps plungers for manual transmissions and up to 19,000 PSI on injection pumps with 11mm plungers in auto transmissions.) The PD Systems are so powerful that they almost double the PSI to a whopping 29,050 PSI +/- of fuel pressure.

150 HP / 320Nm Torque


Pumpe Duese engines are basically upgraded with 4 unit injectors, with each cylinder having its own high-pressure type pump housing 10mm or 11mm plungers. These unit injection nozzles, which are built into a single unit, also eliminate the need for the 4 fuel lines running from the injection pumps of current North American bound TDI's.

In short, Pumpe Duese is simply the name of the fuel injection system within VW's family of TDI engines.

Moreover, this upgrade in injection technology is also supposed to result in a much better burn efficiency with lower emissions to boot.

Keep in mind that while the PD is still a TDI engine, it only has a different more-powerful injection system than what we currently have. VW claims that this type of fuel system is smoother running, except on very hard acceleration or at lower RPM's when the engine is over-stressed or lugged (only then is the PD louder than our current TDI). Other than that, the engine is generally supposed to be noticeably quieter than the currently TDI's available in North America.

One reason why it might be "noticeably quieter" is because the PD system has a better combustion process and needs less compression to get the job done in an efficient manner.

Lower compression with increased injection pressure, means less noise and improved acceleration via more torque.

One drawback to the Pumpe Duese Injection System is the proverbial retarding of the injection timing, which VW uses to further lower NOx emissions - again following the advertising ploy (California & New York) or pattern they're currently using in North America.

See also these excellent articles on: "The Clean Future of the Diesel Engine", Tuneline , The TDI Club's Forum FAQ , and "VW Adds Two New TDI Offerings To the European Lineup".

[ June 07, 2001: Message edited by: Turbo Steve ]

 

[Turbo Steve]

From the Forum FAQ :

"1.9 litre 4-cylinder 115hp 'PD' - again similar to the A4-type engine but with the "pump-nozzle" injection system. Although the peak power is only slightly more than the 110, maximum torque is much higher and the engine has lower exhaust emissions. VW intends to gradually replace the 110hp models with this engine. Not available in North America, reportedly because the exhaust emission controls used on this engine cannot be used with fuels containing greater than 50 parts per million of sulfur, whereas at this writing (1999) fuels in North America can have as much as 500 parts per million.

"Models with this engine have badges with a silver 'T' and red 'DI'.

"The injection system is the 'pump-nozzle' type, and the turbocharger is a variable-vane type. The lack of the injection pump mounted on the front of the engine is the obvious visual difference.

"1.9 litre 4-cylinder 150hp 'PD' - Few details are available at this writing. Models with this engine apparently will have badges with 'TDI' in all red."

 

[SkyPup]

The 150HP PD has 320Nm of torque too.

 

[DeafBug]

TTT

 

[NeXTstep guy]

What is the mileage (L/100km) of the new 100hp PD engines, compared against the usual 90hp engine? Better? worse? by how much?
RWW

 

[AVE_ENG]

If it's just an injection system, than the big question is: can it be retro-fitted?

 

[TDIMeister]

The injection system by itself, definitely NO!

 

[arootbeer]

Notice from the picture that this injection system is driven by a cam (is that a cam?), and is entirely contained within the wet (oiled) side of the engine. Our injection system is almost entirely outside the of the engine, with the exception of the nozzle tips.

 

[harmattan84]

What would it take to retrofit the non-PD to the PD?

 

[mr_sunshine]

think the valve cover could be any bigger?
Uhm.. I imagine someone could use a similar pressurized pump on a non PD engine. The question is, who makes dual pressurized pump sytems for engines this small?

 

[VWannabe]

In response to the person who asked what would it take to retrofit the PD engine, the answer is the engine. The cylinder head itself would be the major piece, but there are probably differences in the block that would have to be accounted for. I don't know this for sure, but it would take so much to switch engine-wise that it would be cheaper to switch the entire engine assembly. Don't forget the ECU as well.

 

[Steve York UK]

arootbeer said:
Notice from the picture that this injection system is driven by a cam (is that a cam?), and is entirely contained within the wet (oiled) side of the engine. Our injection system is almost entirely outside the of the engine, with the exception of the nozzle tips.

Yes - there is a third cam for each cylinder.

 

[pogo]

I remember reading the PD pump was a piezoelectric crystal. Put a current through it and it changes shape, pushing a plunger.

In the the performance forum, someone is undertaking a project to connect a piezoelectric pressure sensor to the glowplug hole in the cylinder, in order to determine the maximum combustion pressure, (and piston angle) in order to try to see how various mods effect actual performance. (pressure deforms the piezoelectric crystal, which generates a current that can be measured)

Can the PD piezelectric injector simultaneously be used to measure the combustion characteristics?

 

[GoFaster]

I would think not, since it's only opening and closing a spill port inside the injector, and it's therefore exposed to fuel system pressure rather than combustion system pressure.

 

[Steve York UK]

GoFaster said:
I would think not, since it's only opening and closing a spill port inside the injector, and it's therefore exposed to fuel system pressure rather than combustion system pressure.

In fact it is not exposed to fuel pressure at all. You can see from the photo of the injector that there is an actuating pin projecting out the side. The piezo solenoid acts on this to close the spill port.

Steve