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Discussion Starter · #1 ·
OK, I am just trialling a simple and inexpensive mod that will enable any PD engine to achieve more oomph....

I can't believe just how easy this is, and hence i will be sharing the 'how to' with you soon.

Additionally I may be able to make the mod switchable and/or adjustable.

I have no idea what the performance gains are, but after a very short punt up the road, the car was noticably more repsonsive over stock.

My car's just had a service, and i'ts noticably brisker anyway, but this mod adds more go!

I'll be posting the results and the instructions on the DIY once i'm happy with it.

This may not be an original idea, but it sure as heck appears to work and i now know how to replicate the device.
 

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quote:

Originally posted by foxy

OK, I am just trialling a simple and inexpensive mod that will enable any PD engine to achieve more oomph....
Excellent Foxy [:)] I will postpone chipping my motor if this works [:)]

edit: maybe you can do a vag-com log to 60-90mph 4th gear pull before and after? Or something similar.
 

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Discussion Starter · #7 ·
Pumpe-Duse TDi's only - SORRY!

Can be installed simply, engines: all the same whether Lupo, Polo, gulf, Bora, Passat, or all other VAG models e.g. AUDI A3, A4, Skoda, Seat, Ford Galaxy.... etc.!

No substantial Soot Increase.

Performance increase:

with 75PS basis on approx.. 95 HP + 35 NM

with 100 HP increse to approx. 120 HP + 45 Nm

with 115 HP increse to approx. 135 HP + 45 NM

with 130 HP increse to approx. 150 HP + 45 Nm

with 150 HP increse to approx. 170 HP + 50 Nm

Increase in output within the VAG tolerances

Noticeably better torque

............................................................

Just been out in mine again in daylight - it's cold and the engine was cold.

Saw some extra soot, but not loads more.

An adjustment to the mod could allow switching between 'stock' and 'mod', so you can avoid extra soot when you wish (like when it's cold).
 

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Discussion Starter · #10 ·
It's the simplest thing EVER!

I will fully test and publish my opinion.

Will try to assemble some diagrams with options so you can do it the very easiest way, or a long-term, more robust version.

Thos: Yes, it's a variation on that theme..
 

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quote:

Originally posted by foxy

Pumpe-Duse TDi's only - SORRY!

Can be installed simply, engines: all the same whether Lupo, Polo, gulf, Bora, Passat, or all other VAG models e.g. AUDI A3, A4, Skoda, Seat, Ford Galaxy.... etc.!

No substantial Soot Increase.

Performance increase:

with 75PS basis on approx.. 95 HP + 35 NM

with 100 HP increse to approx. 120 HP + 45 Nm

with 115 HP increse to approx. 135 HP + 45 NM

with 130 HP increse to approx. 150 HP + 45 Nm

with 150 HP increse to approx. 170 HP + 50 Nm

Increase in output within the VAG tolerances

Noticeably better torque

............................................................

Just been out in mine again in daylight - it's cold and the engine was cold.

Saw some extra soot, but not loads more.

An adjustment to the mod could allow switching between 'stock' and 'mod', so you can avoid extra soot when you wish (like when it's cold).
Foxy (maybe I'm getting ahead of myself here?), can this be in addition to a tuning box? So if my pd 150 has a tuning box + your mod my output will be......? [:D]
 

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Discussion Starter · #17 ·
OK you orrible lot!

THE WAITING IS OVER AND THE DETAILS ARE HERE !!!

IMPORTANT: Modding your car is YOUR responsibility. None of this information holds any kind of warranty. If you break your car - it's YOUR PROBLEM!

This mod has been around for a while in a similar guise for the non-PD engine TDi's and may have been called the EVRY mod.

The following mod is not the same, although the principles are very similar.

Total cost of the most basic form of this mod is less than about £1. (yes a quid or less!!)

Theory: The engine's fuel system uses a temperature sensor on the fuel line to allow the ECU to compensate for the change of fuel density due to temperature increase.

In cold weather, the fuel is more dense, thus needing less of it, and when the fuel is hotter, the converse is true.

The mod 'fools' the ECU into thinking the fuel is stinking hot, and therefore less dense, thus needing more fuel per cycle.

Simply put, the mod involves removing the sensor plug and installing a resistance in it's place.

ENSURE THE WIRING DOES NOT SHORT-OUT or GO TO GROUND (negative/chassis)

This pic shows where the sensor is, under the engine cover.

(Turn off the ignition before disconnecting the plug)

Posted Image


Do not use a resistor of less than 150 Ohm for a PD130/150, and for PD115's, this may be 300 Ohm (depending on outside temperatures)

Posted Image


(The top diagram is the 'stock' illustration, and the bottom is the simplest 'mod')

I have been trialling a 150 Ohm today and ther'es a superb low to mid rev range power and torque increase.

Did a 100 mile trip today, and noticed a little more smoke when cold, and a slight drop in *actual* mpg, with a slight rise in MFA estimated mpg.

This next illustration shows an adjustable version, with a fixed resistor too, to limit the lowest setting and avoid the variable resistor making a short-circuit when on minimum:

Posted Image


I am going to install the wiring for the latter diagram shown here below, to give control over stock / mod and allow an adjustment too.

I am not sure if the switch will be best flicked over before starting the engine as inevitably, the flicking over will break both contacts momentarily, showing open-circuit to the ECU (possibly storing a fault)

Posted Image


I will try and find out the part number for the equivalent mating socket to go with the loom plug (or would welcome any advice - Steve, didn't your version of this mod have a plug and socket? (oh, and by the way Steve, if you measure the resistance across your terminals going to the loom, what do you get? I reckon 150 Ohm !))
 

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Foxy -- thanks very much for posting this and for the very explicit diagrams, impressive stuff. [:D][:D][:D]

It would be interesting to measure the actual resistance 'range' of the fuel temp sensor, to get the true read-out values for ambient temps between, say, -5 celsius and 30 celsius.

I found this just now, about the TD5 motor used in Discoveries:

"The fuel temp sensor is in direct contact with the fuel and measures its temperature continuously between a range of -40°C to 140°C (-40°F to 285°F). If the signal from the fuel temperature sensor is interrupted or corrupted at any time then the ECM will implement a predetermined default value of 60°C (140°F)."

That's a very wide measuring range, and an interesting fixed value.

Once again, great stuff, please keep us updated on your continued findings.
 
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