Turbo Boost Control Soleniod Valve Failure

[guvnar]

Hi all , been a long while since I last posted, still have the thirsty problem but another has cropped up. In the last 2years or so I have replaced the turbo boost control valve solenoid no less than 3 times the latest being last week. I have been to several Nissan dealers with this problem and they assure me it does not exist. However they are quite willing to sell replacement part to me at $165.00 a pop.My question is has anyone had this problem ?. What causes it and how can it be rectified ?.
I have examined the turbo boost valve [the one attached to the turbo] and the connecting rod between the top vac cylinder and the turbo moved up an down at idle speed this seems to produce a drumming sound in the exhaust. I have a race pipe fitted.[no DPF] Can anyone tell me the way that the turbo should normally behave, dealers cant be bothered
I have read most of the posts on the forum and none seem to address my particular quandry. Has anyone got any Ideas. thanks for your help in advance

 

[Old.Tony]

The gold coloured "turbo boost valve" is the turbocharger vane actuator (turbo actuator). In older models (pre 2012) it was vacuum controlled, later models had an electronic actuator.

In the vacuum controlled ones - like mine - you can have the following problems:

* Actuator diaphragm failure. Quite rare.

* Vac hoses deteriorating due to heat. It's common, particularly the connection to the actuator itself because it gets so warm there.

* Boost Control Solenoid failure. This is the sucker you've replaced 3 times, I've replaced mine twice, but the latest time I didn't put another BCS in, I put in a Tillix valve. Can't fault it. It's a common failure point.

* Brake booster vacuum fault. Very, very rare. You can usually tell because your brakes are stuffed and you have hardly any get-up-and-go.

* Vacuum pump failure. Haven't heard of it. It's driven by the primary timing chain, lives down below the fuel pump and has a metal pipe directing the vacuum source up the top above the inlet manifold.

Normal behaviour is as you describe - at idle, the arm moves up and down about 3-5mm constantly. If you remove the hose from the actuator and put one end of a fresh piece of hose on the actuator and suck on the other end, the arm should draw all the way up.

In a recent thread where I discussed buying the Tillix valve, another member here advised that they used a different device on their vehicle. I'd already purchased my Tillix valve, which works fine (no more BCS), but there may be better so hopefully we'll hear more about that soon.

 

[guvnar]

Thanks for the info, much appreciated.where can I find a tillex valve or similar. I will get one and keep it on hand. I don't think the latest replacement will last very long. Have checked all the suggestions in your post and all check out ok. I wonder why Nissan won't admit thers is a fault?

 

[Old.Tony]

Who knows. It's just a valve that oscillates at 100 cycles per second. I suppose it's a plastic housing and could be junk inside. I have two, I should crack one open and take a squiz and see what's in there.

Try www.tillix.com.au, but don't jump before we find out about the alternative - it could be better, the guy uses it on his race cars.

 

[Black_Outlaw]

Was the other device a DAWES valve?

As Tony is aware I threw my BCS away after 2 failed and replaced it with the TILLIX system. This has given me better boost, better drivability and most of all - no random boost spikes / lags like the BCS does.

 

[dilmah]

Ill post a pic tomorrow when I finally get my turbo!

 

[guvnar]

Thanks for the info. will check the Tillex Valve online and wait for further news on the alternative. thanks once again.
P.S. will be out of internet range after wed 13/9 travelling in n/west will go online when / where possible.