Non Return Valves

[racer]

I've been having a high tickover issue, accompanied by an "Idle Control" fault code. Some poking about in the engine bay revealed that air was leaking into the inlet manifold from the EVAP valve vacuum line.

Looking into this further reveals the existence of two grey plastic non return valves, one between the manifold and the EVAP valve, the other between the turbo air intake pipe and the EVAP valve. Extracting the hoses and a bit of experimental sucking and blowing shows that both of these valves are about as "non return" as a length of pipe. Washing them out with solvent has got them working MOST of the time, but they need replacing.

Problem is I can't find a part number for them. The "database that shall not be named" shows the vac hoses for the EVAP system with the valves in it, but not identified. The whole thing is helpfully labelled "hose", and that's your lot.

Anyone know the part number for these things? If not, I'll be replacing them with a couple of Nova brake servo line non return valves!

[SaffronC70]

Hi mate !

I've just discovered the same thing on my car - after spending a long time in Volvo, the valves are £48 each, lmao.

Go with your Nova valves !

My car has had 3 ETMS and this was probably the root cause of the persistant dodgy idle !

Chris

[Engineer]

Hi mate !

I've just discovered the same thing on my car - after spending a long time in Volvo, the valves are £48 each, lmao.

Go with your Nova valves !

My car has had 3 ETMS and this was probably the root cause of the persistant dodgy idle !

Chris

Shame they ain't ECU controlled actuators then your codes would be more accurate but then of course probably £148 plus lol. Mind you though, you might have saved on the 3 ETMS's Chris.

[SaffronC70]

The ECU controlled EVAP valve itself is £21 ! The problem is, £48 includes all the piping; probably worth doing if I wasn't going to scavenge about at work for some valves !

Chris

[Engineer]

The ECU controlled EVAP valve itself is £21 ! The problem is, £48 includes all the piping; probably worth doing if I wasn't going to scavenge about at work for some valves !

Chris

Cheap skate lol. :rolleyes:

[SaffronC70]

Poor apprentice . . . BAA taken over . . . no job in September . . .

[Engineer]

Poor apprentice . . . BAA taken over . . . no job in September . . .

Sorry Chris had no idea. Will you be finished your app. by then?

[SaffronC70]

Sorry Chris had no idea. Will you be finished your app. by then?

No problem, work seems business as usual (I've been off this week) and yes, I'll have completed the AMA by then.

Chris

[Engineer]

No problem, work seems business as usual (I've been off this week) and yes, I'll have completed the AMA by then.

Chris

Wish you luck then Chris being qualified makes the difference. :wink:

[BlackBeast]

So can someone explain what these do and what is the EVAP in the first place? Any chance of getting rid of it?

[SaffronC70]

Hi there

The solenoid EVAP valve vents fumes from the charcoal canister (this absorbs the fumes from the fuel tank?!) back into the manifold at idle (all to do with emission regualtions).

The non-return valves stop the direct link between the intake piping before the turbo and the manifold. An educated guess is the valve allows boost pressure to flow back into the intake rather than force against the EVAP valve.

Hope this helps.

Chris

PS. probably can be ditched, lol.

[BlackBeast]

Thanks Whitey! :)

[T5ER]

seeing as this seems a problem as i have now noticed mine is holding the revs during gear changes if any of you that have had problems going to WD BBQ would be greatfull if some one could point this out to me at the BBQ

[madness]

buy a t4. the valves are 12 quid