Pc007

Hi guys, any idea what's this noise? It only happens on cold startups and it lasts for 3/4 seconds...any idea?

Here's a video I made


Thanks

PAULUNM

SAI pump?

Pc007

Thanks PAULUNM, just googled sai pump and it seems to be the same thing! Thanks

Macster

Would have been better had you started recording before the engine start and left the camera recording at cold start and after for say 30 seconds or longer until the noise stopped or at least the engine idle dropped and the engine smoothed out some.

The secondary air injection pump should come on at cold start and run for a while. About the time the idle speed drops to near normal is about the time the secondary air injection pump is then turned off.

Certainly the noise could be from the secondary air injection pump but it doesn't have to be. The noise could be from something else too.

If the pump is suspected one might be able to find and remove its fuse to disable it and then start the engine under conditions in which the noise always appears and if the noise is absent then one knows.

Pc007

Thanks Macster, the video shows the car on a cold start, the noise lasts for 4/5 seconds...

r6vr6

No MILs on the dash? When my diverter valves went it made that noise on cold starts and at the 1st stop sign or 2 after leaving the house. I had P0491/ P0492 DTC as well. I replaced them and the noise went away as well as the DTCs\ MIL.