Power VIS query

davidos462 · 1st January 2019, 16:57

Hi folks and a happy new year to you all.

I am learning more about my ZT160 every day, mainly through study of the various forums on here. Thanks.

Until last week for example I had never even heard of a VIS part, so in the spirit of enquiry and in hope of curing a inlet manifold rattle, I took the top motor from the power VIS. All seemed OK except that the circular bit with the protuberance that connects with the butterfly slot does not revolve. Surely it should or the butterfly arm would not move. Do I need a replacement and if so any ideas as to best way forward. Would like to use fellow members stock if practical. Thanks for reading and any advice welcome.

rrobson · 1st January 2019, 17:23

Cue mr stocktake but I believe they are a worm drive so you shouldn't be able to turn it. What you need is a vis tester or a t4 to confirm whether or not it's working. You should get a noticable change in engine tone and a slight increase in performance an 4.5k rpm

stocktake · 1st January 2019, 18:07

Evening Reece, hope you and the family are keeping well.

OK David, although the peg you mention is driven by an electric motor the gearing is such that the peg would break before you could apply enough force to cause the motor to move.

There are two Vis motors, power and balance

Inlet manifold rattle is caused the the wearing of the joints of the brown arm that is driven by the Power vis.

Sometimes this is only a slight wear but the noise is amplified as the vis motor has not returned to its rest position and has in effect left the flaps blowing in the wind. I have known many a manifold that rattled go on to give good quiet service when the power vis was repaired. A correctly operating vis will always pull the arm to the drivers side of car every time the car is off. Check to see the position of the brown arm when the vis peg is in the arm slot. .

As you have removed the power vis then look at the brown arm below it. The arm should move freely but firmly from the passenger side to the drivers side of the car. Check for up and down movement of the arm ( floor to sky) any movement or clicking/sloppiness in this action is wear.

if you have a code reader, see if it has codes logged p01471/2 IIRC. If so clear the codes ang then go for a spirited drive and see if these codes return, if so they are your two vis motors.

Many members have vis testers that actually operate the motors when plugged into the tester.

That should be enough to get your teeth into for now see how you go and come back to us

D...

1st January 2019, 16:57	#1
davidos462 Newbie MG ZT 160+ Join Date: Jul 2015 Location: Braintree Posts: 13 Thanks: 2 Thanked 3 Times in 3 Posts	Power VIS query Hi folks and a happy new year to you all. I am learning more about my ZT160 every day, mainly through study of the various forums on here. Thanks. Until last week for example I had never even heard of a VIS part, so in the spirit of enquiry and in hope of curing a inlet manifold rattle, I took the top motor from the power VIS. All seemed OK except that the circular bit with the protuberance that connects with the butterfly slot does not revolve. Surely it should or the butterfly arm would not move. Do I need a replacement and if so any ideas as to best way forward. Would like to use fellow members stock if practical. Thanks for reading and any advice welcome.

1st January 2019, 17:23	#2
rrobson I really should get out more....... 75 tourer cdti, MG ZS 180, nissan terrano & 1.8t rover 25 Join Date: Feb 2010 Location: Pontefract Posts: 2,643 Thanks: 17 Thanked 295 Times in 218 Posts	Cue mr stocktake but I believe they are a worm drive so you shouldn't be able to turn it. What you need is a vis tester or a t4 to confirm whether or not it's working. You should get a noticable change in engine tone and a slight increase in performance an 4.5k rpm __________________ How to view a car - everything you need to help you inspect a used car VIS motor tester avalible to local members Injector removal tool and auto gearbox pressure tester now available

1st January 2019, 18:07	#3
stocktake Vis Whiz Rover 75 2.5 auto Saloon Join Date: Jun 2007 Location: LEEDS Posts: 20,590 Thanks: 2,057 Thanked 3,056 Times in 1,621 Posts	Evening Reece, hope you and the family are keeping well. OK David, although the peg you mention is driven by an electric motor the gearing is such that the peg would break before you could apply enough force to cause the motor to move. There are two Vis motors, power and balance Inlet manifold rattle is caused the the wearing of the joints of the brown arm that is driven by the Power vis. Sometimes this is only a slight wear but the noise is amplified as the vis motor has not returned to its rest position and has in effect left the flaps blowing in the wind. I have known many a manifold that rattled go on to give good quiet service when the power vis was repaired. A correctly operating vis will always pull the arm to the drivers side of car every time the car is off. Check to see the position of the brown arm when the vis peg is in the arm slot. . As you have removed the power vis then look at the brown arm below it. The arm should move freely but firmly from the passenger side to the drivers side of the car. Check for up and down movement of the arm ( floor to sky) any movement or clicking/sloppiness in this action is wear. if you have a code reader, see if it has codes logged p01471/2 IIRC. If so clear the codes ang then go for a spirited drive and see if these codes return, if so they are your two vis motors. Many members have vis testers that actually operate the motors when plugged into the tester. That should be enough to get your teeth into for now see how you go and come back to us D... __________________ Dave... Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident