mistery resistor and disconected vacuum pipes

yendall24

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hi all i was having a look around the engine bay of my 19tdi pd today whilst waiting for the oil to drain and found some wires taped up upon further investigation i found a resistor link on the fuel temperature sender the wires had been cut and linked with a resistor soldered in also found some small vacuum pipes disconected and blanked off one of them went to a small valve just behind the drivers side headlamp and the other went to some sort of valve it was about 2 and half inch diameter and made of stainless steel that sits top left of the engine and as a sort of vacuum activated plunger on it any idea whats gone on here any advice would be appreciated
 
Hi, pictures would help.

Otherwise, we're all assuming, and shooting in the dark.
 
The resistor sounds like that dreadful "max power increase performance" shyte they sell on ebay. It sits on the temp sender and tells the ECU that the engine is cold even when hot so you get overfuelling and a supposed increase in power. Like running the car with the choke out in the good old days. If the previous owner was daft enough to fit that garbage there's no telling what else he's done!
 
hi all i have been looking on the internet and found out that the vacuum pipes disconnected operate the egr valve and egr control selenoid is there a reason for doing this and is there anything to be gained from putting it back to how audi intended
 
As above the resistor is known as the Evry Mod, it modified the value seen by the ECU from the fuel temp sender to increase fueling and thus give you a little more power.

Is it the EGR that has the pipes or could it the the anti shudder valve? Normally in the body of the EGR but closes when the engine is switched off the prevent run on and shudder.
 
the vacuum pipe that is disconected is the one that goes to the top of the egr valve the anti shudder valve is i think a black plastic type thingy attached to the side of the egr body it as a plunger type thing attached to a sort of flap within the egr valve
 
i guess the EGR has been bypassed for the same reason as the fuel resistor, more power.

The egr adds exhaust fumes back into the inlet to lower combustion temperatures and therefore reduce NOx production, however replacing air with exhaust gas means you have less oxygen and therefore less power.
 
its a common mod to disable egr as all it does is recirculate crap and this ends up coating the inlet manifold, it can be adjusted to a very low setting with vagcom if you want to be more technical
i had part of the inlet manifold off recently on my v6 tdi and it was covered in black hardened crap