Breather system / EVAP valve

[Floddy]

I have removed the stock breather system when updating the engine, and everything is just hanging loose right now.

What's good/bad with keeping the PCV valve?

The EVAP solenoid is just hanging loose right now, and I don't have a connection in the new inlet manifold for it. What to do with it? Blank it off? connect it elsewhere? Remove the IM and drill a new bloody hole in it?

I'm totally lost about how the carbon canister works...

[s2avant]

The EVAP solenoid allows vapour from the charcoal filter back into the intake. I won't pretend to know why.

Do you have a vacuum connection on the manifold you could tee into? Otherwise the solenoid will vent fuel vapour into the engine bay which can't be a good thing.

Ben

[Floddy]

Otherwise the solenoid will vent fuel vapour into the engine bay which can't be a good thing.

Well, I'm getting all high on fumes everytime I go for a drive!

I could maybe hook it into the manifold, but I've only got 4mm vacuum connections there, don't know if that's enough? Otherwise I had an idea of venting it off with the breather system.

[s2avant]

That would probably work. I'm not sure how the ECU deals with the charcoal filter system. You would need to make sure that the vapour was well away from sources of ignition.

When it goes into the manifold it doesn't matter but you don't want it frying your new breather setup.

Ben

[Floddy]

Which reminds me, I gotta get myself a big new shiny fire extinguisher...

I just don't understand why the stock breather system is connected to the EVAP valve. Maybe it's just a T-hose for sharing the IM connection.

[s2avant]

I think that is most likely. The two systems are independant.

It's probably a throw back to when they didn't have an EVAP system. Rather than remanufacture the manifold Audi probably just used a t-hose to cut costs.

When I remove my PCV system the EVAP solenoid will be connected straight to the manifold.

Ben

[zlobo]

floddy, this is how i did check the picture http://zlobo.bounceme.net/zlobo/car/engin/DSC01676.JPG

[sailaz]

When I remove my PCV system the EVAP solenoid will be connected straight to the manifold.
Ben

old thread..... but...
which way is proper one to deal with this EVAP ?
In case if VEMS is used and it is not controlling any EVAP valves (I think there is more then one, next to that canister, just is not shown in diagram below ... I'm talking about how this system is done on RS2)
If connect it (No.3) directly to intake manifold so basically it will be like one way valve and will be sucking from that charcoal canister when IM will be under vacuum ?
P.S> PCV system is removed and oil catch tank is installed.

[quattro-nick]

you dont need evap,just connect the plug on the n80 valve(for faulty codes if you drive with origional motronic ecu) and close the lines comming from fueltank and inletmanifold
if you use a stand alone ecu it can be removed all times

[sailaz]

N80 is just hanging right now and I use VEMS, before engine rebuild everything was fine, hmmmmmm.... it means that I have something connected wrongly or some other problem because there is no holes left not connected on IM and there is big vacuum, even BOV stays open when engine is idling ...

[quattro-nick]

BOV stays open when engine is idling ...?????
where did you hook up the little vacuum line?
if you can send some engine and intake pictures we can have a look

[sailaz]

definitely will make pictures, and first off all I will recheck everything slowly and properly because that part wasn't done with paying "enough" attention

[GazzaG60]

the lines on the back of the inlet, the thick one, rubber has a very discreet hole in the side where the line goes. have a look at that.

my inlet is a wagner so slightly different setup my BOV goes to the front side of the inlet. the rest of the lines to the rear

[sailaz]

so .... the pictures ....

thick one only for brakes vacuum:



No. 2 & 3 - one of those going to ECU ? seems that will be plastic one No.3
what for no.4 to left fender ? for cruise control going to accelerator pedal ?



No.7 .... ? ? ?



EVAP solenoid not connected anywhere ... (photo not mine)



THANK YOU IN ADVANCE FOR ANY COMMENTS !

p.s> regarding open BOV (TurboXS Type H-RFL) - it is closing after some rpm applied, might be spring too weak because original was replaced for testing purposes

[sailaz]

... EVAP under hood is gone, now it's ending up below fuel tank inlet,

before


after


is it ok to leave like it is on second photo ?