Questian about green vac line to ECU

[220bhp]

Can anyone tell me if the green vacuum line that runs from the bulk head to the ECU holds vacumm
On my 3b it has been teed of to the boost gauge. I did a suck test on all the lines from the inlet and they all hold, except for the green line Just wondering if this correct.

[GazzaG60]

even though i dont feel it may be best practice but its arguable, i have a t-tree next to the ecu with the eboost and defi boost gauge on it. it never had an issue. all 3 read the same and at least the ecu reading is known and shown.

[Rikki Kitto]

Same as. I T'd my boost gauge right next ti the ECU no problems with it

[220bhp]

Thanks, but should the line hold vacuum.

[Rikki Kitto]

It should be sealed, i.e not leaking

[UrS4boy]

Vacuum Line Info

Can anyone tell me if the green vacuum line that runs from the bulk head to the ECU holds vacuum. On my 3b it has been teed of to the boost gauge. I did a suck test on all the lines from the inlet and they all hold, except for the green line Just wondering if this correct.

Vacuum line info: http://forums.quattroworld.com/s4s6/msgs/188845.phtml

[220bhp]

Thanks for that Dave . Have you high lilted the moisture trap for a reason .My car is a 3b and I think the diagram is for a ann. not sure If there is a difference or not.
I may not have explained my problem properly. So I will try again.

I have the code 00544 boost pressure exceeded I have done several boost leak tests,and cant find a leak .I have changed the DV the MAF no change . I have taken each vac line of the back of the inlet manifold sucked on it , placed my tongue on the end and they all hold on to my tongue ,except for the green line to the ECU. My question is. Should it hold vacuume like the other lines or is it different to the other vac lines in as mush as it is resistant to pressure and not vacuume

[twoqu]

The ecu does sense both boost and vacumm so should hold both!
I would have thought that providing there is nothing else plumbed in to it, there is either the hose itself is damaged, or any of the connctions at the moisture trap (near the ecu) or the moisture trap itself is damaged or the ecu connection both externally at the barb or worse internally as there is a section of hose inside the ecu that feeds the map sensor!

[varia]

Thanks for that Dave . Have you high lilted the moisture trap for a reason .My car is a 3b and I think the diagram is for a ann. not sure If there is a difference or not.
I may not have explained my problem properly. So I will try again.

I have the code 00544 boost pressure exceeded I have done several boost leak tests,and cant find a leak .I have changed the DV the MAF no change . I have taken each vac line of the back of the inlet manifold sucked on it , placed my tongue on the end and they all hold on to my tongue ,except for the green line to the ECU. My question is. Should it hold vacuume like the other lines or is it different to the other vac lines in as mush as it is resistant to pressure and not vacuume

Pauls 3b vacuum

[UrS4boy]

Thanks for that Dave . Have you high lilted the moisture trap for a reason .My car is a 3b and I think the diagram is for a ann. not sure If there is a difference or not.

As others have stated, the pressure/vacuum signal in the green plastic line has to hold both vacuum and boost. If it doesn't then there is a leak. The most common points of leakage are at the moisture trap. The location of the moisture trap varies from B3/B4 to C4 and within the C4 UrS4 to UrS6.

Moisture Trap 101: http://forums.quattroworld.com/s4s6/msgs/20401.phtml

I think the B3/B4 moisture trap is in the left side front side kick panel. Like this:

[newsh]

Should definitely hold vacuum! Lou, I found on my 3B that the hose connection at the ECU would sometimes leak, of course if you're doing a boost leak test you're not inside the car so you don't hear it. The hose had gone hard so even when clamped tight it would still leak.

[220bhp]

Thanks for all the help.I will have to investegate further. Dose anyone know for sure where the moiture trap is on a 3b.

[michaels2s]

official its a water seperator....

[newsh]

Follow the green vac line from the ECU end and you will find it, probably behind the black kick panrel at the bottom of the A pillar.

Mine is in my tool box

[UrS4boy]

official its a water seperator....

Not really. Even auf Deutsch it is "Kraftstoffkondensator".