Ticking Noise When Idling

Maintenance/Repairs
1

My wife’s 2005 Mazda 3 had a bit of a noise on cold start and our mechanic thought it was connected to an intake manifold flap malfunction. Now I notice it seems to have a constant ticking noise at idle. If one of the electrical connections near the intake manifold is disconnected the noise stops. Another forum suggested that connection goes to the solenoid valve. They think that valve may be stuck open and when the connection is taken away it closes and the noise stops. At least that is what I was able to extract from the discussion. Does that make sense? The solutions I saw recommended were to either replace the intake manifold or replace the solenoid valve or don’t do anything because it’s not harmful other than the motor may lose a little bit of power. Any thoughts are appreciated.

2

Some manufactures duty cycle the evaporative system purge solenoid to control flow rate, this creates a clicking rhythm. I don’t know if this is the case on your car. On some vehicles the purge solenoid is covered with a foam/plastic cover to silence the owners but this usually isn’t found on an economy car.

3

Nevada- I will keep an ear out- my wife says the noise is new to her so I am not sure if this is completely normal or not. I am not too worried about it at this point. Thanks for your input

4

Your intake manifold has a flap inside it that changes the intake runner length. Unfortunately when it fails you have to replace the intake manifold. If you unplug the eletrical connector the noise will stop, but the check engine light might come on.

5

Steve- If that is the case and you do not change out the intake manifold what are the ramifications? Does it harm the engine to just let it make the noise?

6

There might be a slight performance loss, but probably not noticeable. It won’t harm anything to let it make the noise, one of my delivery drivers cars has been doing this for over a year.

7

Thanks Steve- I think for now we will just put up with the noise and keep and eye on the performance- don’t really want to pay several hundred dollars for the fix.