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Valvematic ticking or tapping on idle is actually the vacuum pump.


Konrad C
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I have noticed that some owners of cars with Valvematic or Vmatic for short, have queried the tapping or ticking noise coming from the engine during idle. The reason is because of the way the engine has been designed, the throttle is always open so there is very little vacuum produce in the inlet. So a vacuum pump is used to create the vacuum for the brake servo, just like a diesel engine. This vacuum pump will sound louder in a petrol engine, as it is masked by the clatter of a diesel engine. 

The problem is when owners are not familiar with the Vmatic engine, and think the ticking is something wrong with the top end of the engine, as usually associated with worn camshaft.

http://www.toyotaownersclub.com/forums/topic/178167-slight-engine-tapping-valvematic/#comment-1445262

 

So owners of these engine have nothing to worry about.

I will post this in the Auris and Avensis forums which use Vmatic engines.

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On 5/20/2017 at 9:17 AM, Konrad C said:

 

So owners of these engine have nothing to worry about.

I will post this in the Auris and Avensis forums which use Vmatic engines.

Except a tapping noise coming from the engine... the mind boggles!  I wonder where the ex Toyota engineer is working now who designed that system LOL

Still, it's a good wease when your trying to sell a car with an engine knock or a car that slips out of gear... "Oh, that's a feature designed in by Toyota', nothing to worry about old boy!"

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12 hours ago, daveh_rav4 said:

Except a tapping noise coming from the engine... the mind boggles!  I wonder where the ex Toyota engineer is working now who designed that system LOL

Still, it's a good wease when your trying to sell a car with an engine knock or a car that slips out of gear... "Oh, that's a feature designed in by Toyota', nothing to worry about old boy!"

Any other non-Valvematic engine petrol, say VVTi which has top end rattle, will have a problem! Anyway Valvematic engines have covers with that name (Valvematic) on it and the sound comes from the Vacuum pump at end of the cams, on the transmission side. When looking to buy a Toyota with a Valvematic engine, you will probably see a few and then be more familiar with the distinctive sound.

I have heard a rattly VVTi engine that was starved of oil, and that was totally different. Another thing to note is that engine with problems, those sounds get louder, whilst the Valvematic pump does not! If a Valvematic engine has any other tapping or knock, and it comes from different part of the engine, and gets louder with revs, then you have case to say something is wrong.   

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  • 3 months later...

So is this ok to leave on the valvematic engines or will the pump eventually be needed to be replaced?

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