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Old 9th April 2020, 20:19   #21
Cosmin161
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Quote:
Originally Posted by stocktake View Post
Edit, just had a thought, if when you plugged the Vis motor in it is possible the gear over rotates and the cam actually hits both microswitches and then it locks up and will not move as both switches are open. Usually the resistance of the brown arm in the manifold stops this over run. have a quick look
I tested it without the cover mounted on the vis so i saw that it rotates towards one of the switches but not towards the other. I will check the relay.
Thank you
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Old 6th November 2020, 08:13   #22
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Update time
So regarding the topic of this thread, it was the relay on the board. After i changed the relay the vis worked but then after a few tests the dc motor failed.
I left that as it was and carried on with other problems on the car( there wore some) . If you want i can list all the problems that the car had but, at the moment, the only thing not working is the power vis.
The good news is that, since yesterday, the car is registered and road legal.
I’ve read about some upgraded vis motors which i intend to buy because there is a drop of power at low rpm and a revhang that is causing engine brake at some points. I’m suspecting that the power vis might cause these problems since the cars pulls really well above 3000-3200 rpm.
So could you please send me a link from where i could buy the updated power and balance vis actuators?
Thanks!
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Old 6th November 2020, 09:06   #23
vitesse
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Stocktake who has answered your questions also provides the upgraded VIS motors, just click on his name (Stocktake) on the left to send him a PM.

I recently noticed the same lack of power due to a faulty power VIS and I have replaced many for local members. Usually my experience has been that a faulty power VIS doesn't make that much of a difference but on a recent car the power VIS had stopped in the open position meaning that the owner (my daughter) wasn't getting the benefit of the low down torque at 2700 rpm. It was almost like the difference between a 2.0 and a 2.5, once changed it was immediately noticeable.

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Old 6th November 2020, 09:52   #24
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Mine is the smaller 2.0 liter so the impact is greater. I left the intake butterflies on open and at low rpm the engine feels like a 75 hp clio so i allways have to downshift for more power. i will pm stocktake.
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Old 6th November 2020, 11:29   #25
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Mine is the smaller 2.0 liter so the impact is greater. I left the intake butterflies on open and at low rpm the engine feels like a 75 hp clio so i allways have to downshift for more power. i will pm stocktake.
Thanks!
If most of your driving is around town try closing the butterflies (and balance if that's open) by moving the brown arm all the way to your passenger side (closed) the car should then be at max torque at 2700 rpm (2.0 & 2.5). In the medium range the power vis should still be closed but the balance open, now the peak torque is at 4000 rpm for the 2 ltr (3750 rpm 2.5).

The power vis only really comes into action after 4000 rpm - 6500 rpm (2.0)

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Old 6th November 2020, 18:59   #26
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Quote:
Originally Posted by vitesse View Post
If most of your driving is around town try closing the butterflies (and balance if that's open) by moving the brown arm all the way to your passenger side (closed) the car should then be at max torque at 2700 rpm (2.0 & 2.5). In the medium range the power vis should still be closed but the balance open, now the peak torque is at 4000 rpm for the 2 ltr (3750 rpm 2.5).

The power vis only really comes into action after 4000 rpm - 6500 rpm (2.0)

Regards
Thanks for info. The balance vis works so i will try to move the butterflies.
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Old 7th November 2020, 08:41   #27
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The balance vis works so i will try to move the butterflies.
Hello Cosmin,

I'm sorry to say that leaving any of the valves in one position won't be a satisfactory solution. Providing that the balance flap moves freely (they are prone to sticking in the mid position) and the butterfly linkage isn't broken then what you need is a working VIS actuator to restore proper performance to your engine throughout the rev range. As said previously, Stocktake can supply you with the improved version you've heard about.

If you're feeling adventurous, remove the plastic manifold chamber entirely and clean out the carbon blocking the breather pinhole in the RH camshaft cover (the LH can be done much more easily). This piece of maintenance will also enhance the response of your engine.

Simon
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Old 7th November 2020, 19:54   #28
Cosmin161
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Hello Cosmin,

I'm sorry to say that leaving any of the valves in one position won't be a satisfactory solution. Providing that the balance flap moves freely (they are prone to sticking in the mid position) and the butterfly linkage isn't broken then what you need is a working VIS actuator to restore proper performance to your engine throughout the rev range. As said previously, Stocktake can supply you with the improved version you've heard about.

If you're feeling adventurous, remove the plastic manifold chamber entirely and clean out the carbon blocking the breather pinhole in the RH camshaft cover (the LH can be done much more easily). This piece of maintenance will also enhance the response of your engine.

Simon
Thank you for your answer Simon.
I can test if the vis motors are working with my delphi tester. I can hear the balance vis working and the flap shuting closed. The power vis does not work anymore.
The butterfly linkage is in good shape. I,ve checked them when i replaced the timing belts, water pump and tensioner roller. Thats when i cleaned the inside of the inlet manifold. I’ m not sure i understand what you mean by the pinhole of the camshaft cover. Could you please tell me where is that pinhole?
Thanks.
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Old 7th November 2020, 20:15   #29
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The power vis does not work anymore.
The actuator needs renewing then!
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I’m not sure i understand what you mean by the pinhole of the camshaft cover. Could you please tell me where is that pinhole?
I certainly can! Each camshaft cover has two breather tube connections fitted internally with wire mesh filters. If you remove these filters you'll see that behind one of them, the suction connection to the throttle body, is a pinhole restriction. This is what needs clearing.

Simon
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Old 8th November 2020, 05:42   #30
Cosmin161
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The actuator needs renewing then!

I certainly can! Each camshaft cover has two breather tube connections fitted internally with wire mesh filters. If you remove these filters you'll see that behind one of them, the suction connection to the throttle body, is a pinhole restriction. This is what needs clearing.

Simon
Will do, thank you
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