Mivec Owners Group

Hey guys,

I've had my Mirage Asti ZR for about 4 months now...in the last month I've had a ticking/tapping sound develop, and I'm a little mystified about it.

The car performs great, and MIVEC kicks in exactly as it should, no other issues.

When warmed up, i get a pronounced ticking/tapping, that comes in at exactly 1600RPM, and is audible until about 3k RPM, where it either stops, or the noise is drowned out (couldn't say which). The noise increases in speed with engine RPM, however it doesn't get louder. It doesn't sound like a heavy knock or metallic. If i listen to the engine it sounds like its coming from the intake manifold area.

The tapping is barely audible at idle, and the car is idling normally.


Car has had a full service from top to bottom, plugs/leads/oil/filter etc etc, it has also had the valve clearances done. The noise used to be very intermittent, but is now constant when the car is warmed up. It was stood for a couple months before I bought it, and not used that much prior to that...since i've had it I've been driving it regularly, and really made an effort to make sure everything has been fully serviced, and I drive it to it's potential, but only when warm...it pulls brilliantly and has really started to run well and pull better as i've had various things serviced.

My mechanic has listened to it, and says it doesn't sound like anything "engine critical", but the noise is quite pronounced, if it's something relatively simple, it would be great to get rid. He wondered if it's just a characteristic of the engine, but i'm not convinced.

Summary-

-warm engine tick/tap, from 1600rpm upward
-tapping increases in speed with engine rpm, but doesn't get louder
-sounds like its coming from intake manifold area, but hard to tell if this is the source.
-car otherwise in good health


any thoughts?