Air in fuel line

[jordanL]

Hi, I got a 19 plate t6 about 6 weeks ago and now it won't start. It's only done 5k miles. It went back to the garage and they said it was air in the line for some reason. I got it back and the next day it wouldn't start again. I think they're still looking at it but not reqlly telling me much, maybe because there isn't much to tell but I know they spoke about changing the fuel filter incase a seal was broke. I've been told there could be an air leak between the tank and filter. Has anyone else had any similar problems or could shed some light on it? Thanks

 

[jordanL]

It tries to start start so it's not the battery ,it just doesn't fire up.

 

[DXX]

I've been told there could be an air leak between the tank and filter. Has anyone else had any similar problems or could shed some light on it? Thanks

I think they are lost, the lift pump in the fuel tank delivers the fuel to the HP fuel pump via the filter under pressure, if there was a leak the fuel would leak out and that would be obvious.

 

[jordanL]

I think they are lost, the lift pump in the fuel tank delivers the fuel to the HP fuel pump via the filter under pressure, if there was a leak the fuel would leak out and that would be obvious.

Any ideas from yourself then? I have a diesel night heater ,maybe something to do with that?

 

[DXX]

Any ideas from yourself then? I have a diesel night heater ,maybe something to do with that?

Have they scanned for fault codes?

 

[jordanL]

Have they scanned for fault codes?

I think they said nothing was showing so it points to something mechanically. It was someone else who said if the seal on fuel filter wasnt good or if there is a leak , between filter and tank that the fuel would go back to tank. Like you said, you'd expect a fuel leak though. I don't know but maybe something to do with pressure or something when engine is on.

 

[DXX]

@jordanL what was the outcome, cause and remedy?

 

[jordanL]

I've just been told it's ready to collect. Changed an oil filter fuel filter and cam sensor and they've had it for a couple of days starting up hot and cold and say it seems fine.

 

[DXX]

cause and remedy?

So was it air in the fuel system?

 

[jordanL]

Seems there was air in fuel system for some reason and they said the pressure was dropping. I've got it back and seems fine so far, They did the cam sensor so poss more than just the air issue. Fingers crossed issue is sorted.

 

[DXX]

Seems there was air in fuel system for some reason and they said the pressure was dropping. I've got it back and seems fine so far, They did the cam sensor so poss more than just the air issue. Fingers crossed issue is sorted.

There’s a pressure regulator valve on the fuel rail that can leak back to tank, but it doesn’t allow air into the system.

 

[jordanL]

Oo ok would that make the pressure drop then?

 

[DXX]

External leak; I assume none found.
Pressure regulator valve (N276) leaking back to tank.
Leaking injector to cylinder.
Leaking injector back to tank.
Leaking HPFP back to tank.

 

[jordanL]

OK, thanks. I'll keep an eye on it. Cheers mate

 

[jordanL]

External leak; I assume none found.
Pressure regulator valve (N276) leaking back to tank.
Leaking injector to cylinder.
Leaking injector back to tank.
Leaking HPFP back to tank.

Hi, I've had it back in VW and they are looking at it again and there is a visual leak from the top of the tank I think they said but they need to know whats causing it as it only happens when the engine gets turned off.

 

[BenGall90]

Hi all,

I seem to be having a similar issue to this, intermittently not starting, especially if the back end is slightly lower than the front end. No fault codes, just cranks a few times at start and then works absolutely fine when driving. it's very much like the fuel is drawing back to the tank leaving the fuel lines unprimed at start up

It's been in the garage twice for this, they went down the fuel filter route also but it's now happened again since that's been changed.

did you get to the bottom of your issue and find the cause as it's really unsettling leaving town in the van not knowing if it will start to get me back home!


Thanks very much,

Ben

@jordanL

 

[DXX]

Hi all,

I seem to be having a similar issue to this, intermittently not starting, especially if the back end is slightly lower than the front end. No fault codes, just cranks a few times at start and then works absolutely fine when driving. it's very much like the fuel is drawing back to the tank leaving the fuel lines unprimed at start up

It's been in the garage twice for this, they went down the fuel filter route also but it's now happened again since that's been changed.

did you get to the bottom of your issue and find the cause as it's really unsettling leaving town in the van not knowing if it will start to get me back home!


Thanks very much,

Ben

Stick an @jordanL on and they will get notification, not seen on Forum since April 2024

 

[BenGall90]

thanks @DXX , sorted! hopefully he see's it.