Engine: D52447: Vacuum Assisted Engine Mounts & Vacuum System Test

[Ducklakeview]

I think I may also go for the blue or even green hose!

I have a suspicion that my actual turbo governor (No 3) is playing up, as at low speed, the pickup is ever so slightly lumpy and sluggish, and boos level takes a sec or so to rise according to "Torque" on my phone - Gonna order a Dice interface today anyway, so will probably swap the controller for the cheaper one from GSF...

Mike...

[Shadeyman]

Originally Posted by Funky Diver

Cheers for all of this Shadeyman...

6 metres of blue silicon tubed ordered... I fancied a colour change from black, lol

Glad someone found it helpfull.

I did concider replacing mine with a colours.
For example:
Main feed from Vacuum pump to the T piece in red.
Feed from the T piece to the boost control valve and turbo actuator in green.
Feed from the T piece to the engine mounts and their control valve in yellow.

But couldn't make my mind up which colours would be best suited so ordered all black. lol

Originally Posted by Ducklakeview

I think I may also go for the blue or even green hose!

Upload a few pics so we can see how it looks.

Originally Posted by Ducklakeview

I have a suspicion that my actual turbo governor (No 3) is playing up, as at low speed, the pickup is ever so slightly lumpy and sluggish, and boos level takes a sec or so to rise according to "Torque" on my phone - Gonna order a Dice interface today anyway, so will probably swap the controller for the cheaper one from GSF...

Mike...

I replaced mine a few days after buying the car. Replaced the MAP sensor to as it controls the boost control valve(No 3).
http://www.volvoforums.org.uk/showth...+control+valve

[Shadeyman]

My XC90 had/has a slight boost delay too, I reduced it to almost nothing, doesn't bother me so will do something about it eventually, no rush. I've serviced the whole vaccum system replacing some of the parts so I think there can be only 2 things causing it.

I think the problem is the vanes in the turbo are not closing enough at low engine RPM to maintain a high turbo shaft RPM. If the turbo shaft is spinning to slowly when engine RPM is low, boost takes longer to increase. Variable Vane Turbos are supposed to limit turbo lag to almost nothing by keeping the turbo shaft spinning at high rpm.

So the causes:

1. Low vacuum caused by the vacuum pump itself. If its too low the actuator wont close the vanes to increase the velocity of the exhaust gases hiting the turbo impeller. I've monitored it and it does drop quite low sometimes for no reason. I'm guessing worn/faulty valve in the the pump itself could be the cause.

2. The vanes in the turbo are sticking momentarily, probabely due to carbon deposits.

[niallcook]

Sorry to resurrect this thread, but I'm hoping it might help with some of the turbo problems I have been experiencing.

I have replaced the air intake pipe (nice hole in it), cleaned the EGR, cleaned the turbo control governor (which got rid of the rasping noise) and connected the oil return pipe under the turbo properly after the garage bodged it. But the symptoms that remain are very similar to this thread: engine service required comes up under hard acceleration, no power, etc.

I don't have a vacuum gauge to test things, but have tried the following (sorry if I have got the official part names wrong):

Hose from engine pads to engine pad valve (the one that hangs on the air box) connected at bottom + hose from vacuum pump to engine pad valve connected at side = engine service required light on under hard acceleration + hardly any power on acceleration.

Hose from engine pads to engine pad valve blocked + hose from vacuum pump to engine pad valve connected at side = no engine service required light but still no power on acceleration.

Hose from engine pads to engine pad valve connected at side + hose from vacuum pump to engine pad valve connected at bottom (i.e. swapped around) = no engine service required light, better power, but still doesn't feel right.

What do you guys think? Could the engine pad valve be shot? Any way of testing it? Or should I just replace all the hoses and see if that improves anything? Or is the turbo just on its last legs?

[bobdabuilda]

Thanks for all the info you posted Shadeyman. I have noticed a low rumble noise and increased cabin vibration when the car is idling and thought I'd check out this vac system but unfortunately I don't have a meter.

I disconnected the electrical plug to part 5 (pad control solenoid or this part http://www.ebay.co.uk/itm/Genuine-Vo...-/190710122177 ) on your diagram and the vibe and noise was much reduced. I then reconnected the plug whereupon the noise returned so I then disconnected the pipe to the front and rear vac mounts and again the noise virtually disappeared. The suction from the lower port of part number 5 was still there at idle and went at around 1250 revs as you mentioned so from this I'm assuming that the problem with vibration and noise is being generated from either or both of the front & lower engine vac mounts.... Did you replace both mounts and if so is it an easy DIY job or did you go to a decent indy to get it done- if so how much did it cost roughly please? Does VIDA provide any info on the vac mount system in terms of pressures etc? tia

[Shadeyman]

Originally Posted by niallcook

What do you guys think? Could the engine pad valve be shot? Any way of testing it? Or should I just replace all the hoses and see if that improves anything? Or is the turbo just on its last legs?

Replace all the small bore pipes and make sure its piped correctly using the diagrams in this thread. Then take it for a thrash on the motorway, burn any carbon deposits of the vanes of the turbo, test to see if there is any improvement.

Originally Posted by bobdabuilda

Did you replace both mounts and if so is it an easy DIY job or did you go to a decent indy to get it done- if so how much did it cost roughly please? Does VIDA provide any info on the vac mount system in terms of pressures etc? tia

Once I'd replaced O-ring on the brake servo side and all the small bore pipe used on the vacuum system it cured the vacuum leak. I was expecting to have to replace the rear vacuum mount but the system is fine now so I never had to replace the mounts.

That said replacing the front vacuum mount would be a relatively easy job, just support the weight of the engine on a jack, but access to the rear vacuum mount is difficult, just replacing the small bore pipe to it was a pain in the a*s so I'd recommend you purchase you own Genuine Volvo mounts and use a trusted indy to install them ...

I still have 2 brand new mounts(£90 each) sitting on the self in my garage but so far everything has been fine ...

After a service, replacing the O-ring on the brake servo side this is what I get when connected direct to the vacuum pump. I'm sure my problem was a combination of small bore pipe leaks, a leaking O-ring on the brake servo and I suspect the vacuum pump wasn't being properly lubricated, may be low oil level or incorrect viscosity, engine mounts seem fine.
Click on the image below to watch the video.

[bobdabuilda]

Thanks, what make & how much is that meter that you are using please?

I took it a step further and clamped off the pipe to the front mount and the vibration/low rumble noise went so I assumed that the front mount was the problem, but when I clamped off the rear mount pipe the noise initially got louder for about a second and then also went quiet which I wasn't expecting. I'm wondering whether there is a slight leak in the front mount which seals off when the diverted vacuum power is increased by clamping the rear mount pipe making the bush softer and more collapsible? A long shot I know but it doesn't make sense otherwise.

In summary

Common pipe from solenoid controller unplugged or blocked= no noise

Solenoid controller unplugged = no noise

Pipe to front mount clamped= no noise

Pipe to rear mount clamped= initial increased noise for about a second and then quiet.

All pipes look to be in good condition and it is an 07 year with 90k on it.
Where did you source your 4mm silicone pipes from and are your £90 mounts genuine volvo ones sourced from Rufe at FRF?

[Shadeyman]

Originally Posted by bobdabuilda

where did you source your 4mm silicone pipes from and are your £90 mounts genuine volvo ones sourced from Rufe at FRF?

eBay and yes they're Genuine Volvo. Plenty on there, here's a few ...

Vacuum pipe:
http://www.ebay.co.uk/itm/201123837967

Front mount:
http://www.ebay.co.uk/itm/191295187856

Rear mount:
http://www.ebay.co.uk/itm/191295191090

[Shadeyman]

Originally Posted by bobdabuilda

Thanks, what make & how much is that meter that you are using please?

eBay again ...
http://www.ebay.co.uk/itm/130904563689

[bobdabuilda]

Awesome cheers. One thing I noticed when I disconnected the vac pipe of the F&R mounts to the turbo control valve/solenoid the noise was pulsatile like a garden sprinkler spinning around rather than a constant hiss that I would expect (which it is when I disconnect the other pipe going into the solenoid controller) . Is this normal?