Citigoists - show me your hoses

[Stonster]

Following on from my search to try to solve stop-start restarting issues, I'm still trying to find the problem.  I've checked the wiring to my brake booster pressure sensor, and the sensor itself was also replaced.  Now trying to check all the hoses for a leak.  I'm looking at one of the connections of the vacuum hoses and it looks a bit odd to me... I'm just wondering if this might be the cause of a vacuum leak?

 

I'm just hoping a couple of folks might be able to send me a photo of their connection so I can compare.  I had to hold my phone over it on macro mode, but it wasn't too tricky to get a clean shot. 

 

It's the connection to the right of the engine, near behind the air filter:

 

My connection looks like this - are the black clips meant to be together? 

 

[Breezy_Pete]

Never seen anything like that, but I'd say 'without doubt'.

[peter3197]

That is definately wrong, I've just checked mine. Those flanges should be flush.

[Tech1e]

Yep, just needs to be pushed in a little further

[Stonster]

12 minutes ago, peter3197 said:

That is definately wrong, I've just checked mine. Those flanges should be flush.

Thanks mate - I can't see from your photo but are the plastic clips clipped together?

[peter3197]

Just now, Stonster said:

Thanks mate - I can't see from your photo but are the plastic clips clipped together?

Yes, you can see on the photo that the flanges are flush, it's chucking it down outside now and I couldn't get my phone at the right angle.

[Breezy_Pete]

@Stonster please let us know when/whether this 'clippage' solves the problem.  Partly so others can look for the same cause if they have similar troubles but also for the more general reason that it will be interesting if this 'absolutely not electrical' fault can be demonstrated to cause fault codes that include one that explicitly said 'electrical fault in circuit', IIRC.

 

[Stonster]

2 hours ago, Wino said:

@Stonster please let us know when/whether this 'clippage' solves the problem.  Partly so others can look for the same cause if they have similar troubles but also for the more general reason that it will be interesting if this 'absolutely not electrical' fault can be demonstrated to cause fault codes that include one that explicitly said 'electrical fault in circuit', IIRC.

 

Will do. Just need a dry day to get out and play! Current plan is to gently heat the hoses with a hot air dryer to try to get them together more easily. I've also bought a second hand sensor to check the voltage values in comparison

[Stonster]

So frustratingly connecting the pipes more closely didn't resolve the issue. It's really weird - the way the sensor is acting (restarting the car after 20-40 seconds) suggests a drop in vacuum from a vacuum leak. But I can't feel this at all in the brakes. If there were a leak I would expect the brakes to get harder when the engine is stopped... But there's no feeling of this...

 

Two thoughts:

1. Could there be a vacuum leak that's small enough not to feel at the pedal but big enough to set the sensor off?

 

2. Is there another non return valve in the servo? Then if I had a leak

 I'd only be losing vacuum in the pipe but not in the servo. Can't see why the system would need two valves though.

 

I probably need to disconnect the hoses the check the non return valve, but I'm a bit nervous because they feel pretty stiff and I don't know how easy it is to connect/ disconnect them

[J.R.]

It absolutely makes sense to me that there would be 2 seperate not connected vacuum systems both with non return valves to avoid brake failure when there is a problem like this.

 

Cant say for sure that your car is designed that way but would stake my house on it.

 

I bought a Mytyvac when I saw just how much vacuum operated emissions junk my vehicle had.

[Breezy_Pete]

Bold staking!

[Stonster]

Well there's only one vacuum pipe to the brake servo... It's just whether the servo has a separate non return valve in it...