Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Northstar on 12 May 2008, 21:14:34

Title: Strange wizzing noise from cold start.....
Post by: Northstar on 12 May 2008, 21:14:34: Hello all....

My Omega has started to make a very strange noise when its started from cold....

Sounds like a high pitched wizzing noise.... Like the noise you get from a super charger.
After a minute or so it goes off, as if a valve had been closed or summat.....
Its been doing it for a few months now, but seems to be getting louder??
Im guessing its something to do with the choke?? Is it something to worry about??
Title: Re: Strange wizzing noise from cold start.....
Post by: Dazzler on 12 May 2008, 21:19:07: Its normal matey ;)

Just a fan that runs for the first minute or so, does tend to get a little noiey with age.
Title: Re: Strange wizzing noise from cold start.....
Post by: Northstar on 12 May 2008, 22:29:17: Ow cool thanks....

What does it do just out of interest??
Title: Re: Strange wizzing noise from cold start.....
Post by: TheBoy on 12 May 2008, 22:32:55: sia - pumps air into exhaust manifold which ignites with unburnt rich fuel to heat cats quicker
Title: Re: Strange wizzing noise from cold start.....
Post by: Northstar on 12 May 2008, 23:22:02: Thanks for explaining that one... cheers :y
Title: Re: Strange wizzing noise from cold start.....
Post by: Darth Loo-knee on 12 May 2008, 23:31:59: You can unplug it mate.... its under the passengerside wheelarch, infront of the wheel..... :y
Title: Re: Strange wizzing noise from cold start.....
Post by: Northstar on 13 May 2008, 00:05:41: Will that have any effects at all??
Title: Re: Strange wizzing noise from cold start.....
Post by: Darth Loo-knee on 13 May 2008, 00:09:15: only the noise will stop ;D
Title: Re: Strange wizzing noise from cold start.....
Post by: Darth Loo-knee on 13 May 2008, 00:10:54: I have taken off the secondary valve and pipe off too, then blocked the rubber hose ends up...
Not noticed any difference at all :y
Title: Re: Strange wizzing noise from cold start.....
Post by: Northstar on 13 May 2008, 00:11:21: ::)Nice one.....

Its something to tinker with I guess... lol...

thanks once again.
Title: Re: Strange wizzing noise from cold start.....
Post by: bappy on 13 May 2008, 19:15:29: I noticed this noise on mine.... At risk of sounding like a complete retard.... doesn't deliberately burning fuel in the manifold cause potentially a lot of extra wear on the cats? at £200+ each I dont want my car deliberately wearing out cats for the sake of cleaner emmissions 2 miles sooner....
Title: Re: Strange wizzing noise from cold start.....
Post by: Grumpy on 13 May 2008, 19:40:41: Quote
I noticed this noise on mine.... At risk of sounding like a complete retard.... doesn't deliberately burning fuel in the manifold cause potentially a lot of extra wear on the cats? at £200+ each I dont want my car deliberately wearing out cats for the sake of cleaner emmissions 2 miles sooner....

You are not burning extra fuel. You are burning any excess fuel that
has come through whilst running on a richer, colder mixture during
start up.

The theory is that the Cats get up to temperature quicker. Cats
are efficient when hot, not cold.
Title: Re: Strange wizzing noise from cold start.....
Post by: bappy on 14 May 2008, 12:42:18: true but it's still unburnt petrol being ignited in the manifold isnt it?

My understand of exhaust systems is very limited so I can accept it if im wrong lol
Title: Re: Strange wizzing noise from cold start.....
Post by: jasonxr2racer on 14 May 2008, 13:30:21: Quote
I have taken off the secondary valve and pipe off too, then blocked the rubber hose ends up...
Not noticed any difference at all :y
Solves a problem for me!!!

Is the secondary one behind the rad with 2 vac pipes attached and a sensor with grey plug?