Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: omegapete on 31 August 2010, 23:04:34

Title: Strange jet engine type noise after start up.
Post by: omegapete on 31 August 2010, 23:04:34

Hi, when I start my Omega 2.5 petrol I get a strange jet engine type noise which lasts for 2 or 3 mins. then shuts down. I think it has something to do with recirculating something to make it greener. As it seems to be lasting for longer I was wondering if it was possible to disconnect it without doing any harm to the car and if so how to go about it, and if it is possible would it bring warning lights up on the dash. Any help much appreciated.Thanks...

Title: Re: Strange jet engine type noise after start up.
Post by: Mr Skrunts on 31 August 2010, 23:09:46

Sounds like the SAI if I have the right term for it, I think others have disconected it without out issue but am sure someone will confirm later.

Title: Re: Strange jet engine type noise after start up.
Post by: RobG on 31 August 2010, 23:11:40

Unplug it. Lives under passenger front wing

Title: Re: Strange jet engine type noise after start up.
Post by: dbr on 31 August 2010, 23:19:32

Friend of mine had the same. Mine has never made the noise......might be bust!!

Title: Re: Strange jet engine type noise after start up.
Post by: aaronjb on 31 August 2010, 23:29:32

As others have said - SAI (Secondary Air Injection); it's job is to 'inject' (read: blow) fresh air onto the front of the CATs during cold start conditions (on other cars with this system the ECU also slightly richens the mixture during this time, too - I presume the Omega is the same).

It does this because the combination of fresh air and rich mixture brings the CATs up to operating temperature much faster - it's an emissions control measure to reduce emissions when the CATs are warming up (I forget if it was introduced to meet US or Euro standards)

Replaced on a number of newer marques by 'Pre-CATs' which are closer to the engine (usually in the manifold) to heat up in the first 30 seconds of running to meet Euro 3/4 and US ULEV emissions standards.

Anyway.. short version - disconnect it and do away with it. It won't affect your MOT (which measures only 'up to temperature' emissions) and it won't throw an Engine Check light :y

Title: Re: Strange jet engine type noise after start up.
Post by: omegapete on 02 September 2010, 22:24:40

Thanks for your prompt replies, I,ll give it ago and see what happens. CHEERS.

Title: Re: Strange jet engine type noise after start up.
Post by: Broomies Mate on 02 September 2010, 22:35:37

Quote

Thanks for your prompt replies, I,ll give it ago and see what happens. CHEERS.

You'll find the pump up in the front bumper, just infront of the passenger wheel arch liner.  Unplug it and cable tie the plug safely out of the way.  :y

Title: Re: Strange jet engine type noise after start up.
Post by: Squidy on 03 September 2010, 07:38:08

dont want to hijack thread but other than the obvious start up noise, is there any other advantage to disconnecting this?  :-?

Title: Re: Strange jet engine type noise after start up.
Post by: 2woody on 03 September 2010, 08:39:33

no - none

Title: Re: Strange jet engine type noise after start up.
Post by: Jinglemaster2 on 03 September 2010, 10:39:47

Quote

dont want to hijack thread but other than the obvious start up noise, is there any other advantage to disconnecting this?  :-?

Your grandmother will deflate and the cat will chew its own head off.

On a more serious note, you will use slightly less electricity.

Title: Re: Strange jet engine type noise after start up.
Post by: bigdods on 03 September 2010, 12:33:41

I just pulled the fuse when mine started getting noisy, didnt cause any problems.

Title: Re: Strange jet engine type noise after start up.
Post by: Jinglemaster2 on 03 September 2010, 12:37:28

When mine got noisy, we just burried her.