Loud humming sound at startup

[rolls 912]

I'm absolutely miffed - there's a loud humming sound that lasts for a few minutes at startup on my 3.2. As you face the engine it's coming from the far RHS behind the air meter. Would it be in the vicinity of the oil cooler?

Any thoughts?

[steely]

Just a WAG - dis-engaged, but running, starter?
Can't think of anything over there.

[wildcat077]

Just a thought here but how old is your fuel pump ?
They start to hum pretty loudly before they let go ... i know the sound would be coming
more from the front of the car but the vibrations can transmit and be misleading as to their
location.Mine did just that !

Cheers !
Phil

[E Sully]

Ambient air valve located just above the oil filler neck.

[kidrock]

Originally Posted by E Sully

Ambient air valve located just above the oil filler neck.

+1. Does it sound like a kazoo?

[rolls 912]

Thanks for the replies

Ambient air valve. Ill check that out. Is that the one that is shaped like a mushroom? The whir sound is more mid range rather than high pitched.

Fuel pump is new although will check.

The sound is very loud in the cabin. Bordering extremely loud. Funny though because from the engine bay with the engine running, its only just audible. I might try the piece of hose to the ear trick tonight.

Could it be the oil pump? its the only item that I can think of that oscillates in that part of the engine area that could make such a sound.


R

[kidrock]

Originally Posted by rolls 912

Ambient air valve. Ill check that out. Is that the one that is shaped like a mushroom?

yes

[rolls 912]

Could I ask ,what dose this valve do?

[kidrock]

Search, and ye shall find, my brother.

Ambient Air vlave question

[steely]

I thought they brought in warm engine air to the TB for starting in cold weather.

I reckon it is winter there?