TDI 110 vacuum system and other diagrams

[Muttley]

A while ago I was trying to trace a vacuum system pipe, to see what would happen if the EGR valve vacuum feed was disconnected and not properly sealed. I found there were no diagrams of the vacuum system as a whole, just odd bits of it here and there. The only thing left was to go out with a clipboard and trace the various little black pipes to see if it all made sense.

The diagram I came up with is attached. It is of the system as fitted to my ASV (a TDI 110) engine. Should be pretty close for TDI 90's and 110's, less so for PD's and much less use for petrol engines.

On the same page there is a block diagram of the gas flow through a TDI engine, and an attempt to diagram all the signals to and from the ECU; no warranty expressed or implied

Please let me know of any errors or omissions and I'll correct the diagram.

 

[allh2k]

wow

that makes no sense to me! but looks great thanks from a ASV owner

wait a minute is the black line wires on the first diagram? and the black line air on the last diagram?

 

[Muttley]

OK. There are three diagrams (sorry for not being properly structured)

The large diagram at the top is a diagram of the hose connections in the vacuum system. Each black line is a vacuum hose, the blue ones are "ambient-pressure" hoses from the airbox to the N18 and N75. (N18 and N75 switch between atmo and vac to vary the pressure applied to the actuators, so as to vary the position of the turbo vanes and the EGR valve). In the car, these are narrow black flexible tubular hoses.

In the lower right diagram the lines are gas pipes - either inlet tract or exhaust pipes. Air comes in at top right and exhausts at lower right. The diagram was drawn to make clear the order of bits in the gas flow i.e. the MAF is before the turbo, the EGR is after the turbo - etc.

The lower left diagram is a block diagram of the sensors and signals going to the ECU, combining information from books, publications and other sources. Sensors provide information to the ECU (inward arrows), which controls the engine through signals to various actuators (outward arrows).

I've made some corrections already. Once I've got any further feedback from this thread, I'll do a final edit and get it posted.

 

[tolly_tdi]

cheers muttley, posting great stuff as usual!

 

[Robb1990]

What diameter is the stock Vac hose? I wouldnt mind replacing it with some nice red stuff and that diagram makes things soo much easier! Thanks mate

 

[trinialhambra]

Theres a vacuum line that runs from just after the intercooler that apparently seems to be routed INTO the cabin via the firewall, what line is that because it looks as if it need replacing on my Alhambra TDI

 

[Muttley]

trinialhambra, can you get a picture of the "vacuum line"? From your description I'd say it was a pressure line leading to a boost gauge, which would be an aftermarket addition by a previous owner, perhaps?

 

[M1KEH]

I think trinialhambra has an early alhambra with the MAP in the ecu muttley. I maybe wrong though.

 

[trinialhambra]

1999 or 2000 TDI 1.9 Alhambra

 

[leontdisx]

hi. you guys might be able to help. the pipe that comes out of the brake servo and along the bulkhead to an item attatched to the cylinder head with part numbers

LUK

VAPEC 143

WW0 038 145 101 B

RE 2180-01

im not sure what this is?? some sort of vacuum pump?

anyway the pipe goes into that and the bit of pipe that goes from the servo to a conection along the way to that item has a split in it. anyone know what that pipe is called/ for?? vaccum for the servo but any other name?

thanks
james

 

[MJ]

the pump on the head is the vac pump, the pipe in question is the brake servo vacuum pipe.

 

[leontdisx]

ideal, thanks. its split exactly where seat said it would in the recall and they want me to pay over £50!! for the hose so i think im going to try and argue that if it was recalled for that reason and mine is showing it where seat said it would then surely its got a defect!

 

[leontdisx]

talked to seat and they said it didnt effect my model year of car!
obviously it does, they want 50 quid for the bit and over 80 quid to fit it! it wont take 2 mins to fit wont it??
james

 

[MJ]

2 minutes to fit and it was mainly mk3 ibizas that were effected.

 

[sssstew]

yep correct the recall was done on the mk3 ibizas back in 2004/2005, i had mine replaced.

 

[WhatTheHell...]

helpful diagrams, thanks.