[Mk2] [NA] Ticking Noise from Inlet - Help identify it please?

[jason_pmr2]

My inlet manifold has been ticking for some time.
After investigation into the cause, and some fiddling with the vacuum hoses to make sure the tvis system is operating properly I have managed to get the ticking to stop but only when i remove the vacuum hose from this pressure regulator thing:


now when i remove this vacuum hose, this shaft moves:

and the ticking stops completely?

This regulator thing opens and closes the butterflys in the inlet manifold at higher revs if i remember rightly - to help low down torque.
But why is it ticking? And why does it stop ticking when the butterflys open?
Now its only been doing this since a head gasket change - but i have double checked that all the vacuum hoses are deffo in the correct place.
Could i just remove the vacuum hose so it stops ticking?

Could someone please advise?[/img]

[mr2magic]

Just a thought:

Remove the TVIS System completely and check the screws holding the valves to the center shaft! Could be one is working loose. YOU DO NOT WANT THIS TO HAPPEN!

It may be something else entirely but a check can't hurt.

[g.lewarne]

its not TVIS on an NA, its ACIS

but regardless, mine used to tick a bit, and after removing the ACIS cover to clean / degunk and fit a new gasket, i noticed that the clip which connects the two shafts in the middle was loose and wibbly. Popped it off, squeeze with pliers, pop on and no more ticking.

[Fourveesix]

The ticking noise is created by pressure wave action in the intake manifold as the valves open and close.
Gas pulsations (pressure variations) acting on the butterflies and creating a noise due to the suggested slack in the mechanism.

[jason_pmr2]

Removed the ACIS over the weekend - and it was the clip holding the two shafts together. Tightened it up and has stopped ticking now.

Thanks again!

Im tempted to take the butterflys out completely- having read some dyno printouts, it does little to increase the low end torque - Hardly noticable - so may just strip it all out.

[g.lewarne]

cool, glad you sorted it.

its not worth removing the butterflys, if you want to experiment just pop the vac line off the actuator and block it. the default position of the butterflys is open, so if the actuator isnt actuated they will stay open. its easier to change it than removing the cover just to find that you prefer it one way or the other


be aware though that you will lose that lovely kick @5000 rpm if you disable it. thats the most fun part!