Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: moorej91 on 03 May 2007, 22:41:14

Title: Noise on startup, goes after 30 seconds
Post by: moorej91 on 03 May 2007, 22:41:14
Hi, This is my first time on here. I purchased a 2.0 omega estate automatic about 3 weeks ago. When I first start the car up there is a "whurring" sound for about 20 to 30 seconds then it stops and is quiet. It is not engine rev related and does not seem to affect engine performance. Over the last couple of days it seem to get worse. It has been mentioned that it might be the fuel system pressurising itself.
Any help would be appreciated.
Title: Re: Noise on startup, goes after 30 seconds
Post by: Chopsdad on 03 May 2007, 22:46:19
Does the noise come from the engine bay? or could it be the vents opening inside the cab for the air con system?
Title: Re: Noise on startup, goes after 30 seconds
Post by: Craig_R on 03 May 2007, 22:52:57
The one thing i can think of it being is the secondary air injector pump is on its way out

Dont worry about replacing it do some searches on secondard air injector pumps and you will know what i mean
Title: Re: Noise on startup, goes after 30 seconds
Post by: Matchless on 03 May 2007, 23:36:36
It sounds like the secondary air injection pump mounted under the front of nearside front wing. The bearings in these get noisy. Find the pump, its above the horns, reach up and there is a connector on top of it. Unplug the cable and see if that stops the noise.
You dont need this system for Mot so can leave it disconnected but its best to blank-off the pipe where it leads to the exhaust manifold.
Title: Re: Noise on startup, goes after 30 seconds
Post by: wastedperfection on 03 May 2007, 23:40:29
Mine does it (2.5v6 manual)

Isnt it the fan just doing some sort of self test?

It is definitely coming from the fan that cools the engine

Matt
Title: Re: Noise on startup, goes after 30 seconds
Post by: TheBoy on 04 May 2007, 09:38:51
Quote
Mine does it (2.5v6 manual)

Isnt it the fan just doing some sort of self test?

It is definitely coming from the fan that cools the engine

Matt
Are you sure?  Secondary Air Injection pump, as described by Matchless above, is the most likely candidate...
Title: Re: Noise on startup, goes after 30 seconds
Post by: Dazzler on 04 May 2007, 11:06:52
Secondary Air Injection pump, as described by Matchless above, is the most likely candidate...

I agree, mine does exactly the same, nothing to worry about ;)
Title: Re: Noise on startup, goes after 30 seconds
Post by: STMO123 on 04 May 2007, 11:28:28
....only when it's cold outside.
Title: Re: Noise on startup, goes after 30 seconds
Post by: Matchless on 04 May 2007, 13:54:02
Quote
....only when it's cold outside.

No. The ECU will turn the pump on at every start-up and turns it off when lambda sensors start working properly or a time-out occurs, whichever is the soonest.
Takes longer to heat the exhaust and lambdas when its cold so pump will run for longer.
Title: Re: Noise on startup, goes after 30 seconds
Post by: moorej91 on 04 May 2007, 17:02:53
Thankyou for everyones reply, wish I had joined sooner. I am not exactly sure where the noise is coming from, but it does sound like it is more to the nearside front wing as suggested by some of you. Will it be a problem if it fails, will it let me down. I dont know wether it is connected but The engine electronics warning light came on today and stayed on. When I restarted the car after about 2 hours the light went out as usual.
Could this be a problem waiting to happen. How much could I expect to pay if it is the secondary air pump? Could you tell me of a reliable garage in the cannock staffs area that do a good job and are competitively priced.

Thanks again all
Title: Re: Noise on startup, goes after 30 seconds
Post by: rpont on 04 May 2007, 18:47:38
Could be a hole in the air hose that goes from the vacuum valve mounted at the top of the radiator fan to the non return valve. Mine has failed twice and always blew the hole in the underside so that you couldn't see it. Eventually discovered that the metal non return valve had failed allowing hot exhaust gasses to the pipe.
Title: Re: Noise on startup, goes after 30 seconds
Post by: TheBoy on 04 May 2007, 21:43:24
Quote
Thankyou for everyones reply, wish I had joined sooner. I am not exactly sure where the noise is coming from, but it does sound like it is more to the nearside front wing as suggested by some of you. Will it be a problem if it fails, will it let me down. I dont know wether it is connected but The engine electronics warning light came on today and stayed on. When I restarted the car after about 2 hours the light went out as usual.
Could this be a problem waiting to happen. How much could I expect to pay if it is the secondary air pump? Could you tell me of a reliable garage in the cannock staffs area that do a good job and are competitively priced.

Thanks again all
To find out why eml came on, do the 'paperclip test' and report codes back here...
Title: Re: Noise on startup, goes after 30 seconds
Post by: moorej91 on 04 May 2007, 21:55:51
I used to do the maintanence on all my old cars when I was younger, but not recently. Could you tell me what the "paperclip test" is, I pressume its to short out and overide something but what.

Regards
Title: Re: Noise on startup, goes after 30 seconds
Post by: TheBoy on 04 May 2007, 22:02:01
Quote
I used to do the maintanence on all my old cars when I was younger, but not recently. Could you tell me what the "paperclip test" is, I pressume its to short out and overide something but what.

Regards
Yes, details in FAQ section :)
Title: Re: Noise on startup, goes after 30 seconds
Post by: curly on 04 May 2007, 22:33:52
hi there,the noise you are expereancing on start up is the secondary pump that runs for anything up to 60 seconds depending on out side temp,from inner wheel arch area that actually is a cat converter pre heater so it gets the cat/s warmed up quicker than the engine can to bring the lamda sensors in operation quicker and thus gives you economy and low emissions in a reasonably quick time,and stops it running to rich,which is why when you start up the idle should be about 1200rpm,then when pump stops drops to850rpm,then temp gauge moves up normal 700rpm (v6)so it stops stalling through ecu,so in a nutshell perfectly normal on all models inc vectra/astra,hopr this helps you ,good luck,curly.
Title: Re: Noise on startup, goes after 30 seconds
Post by: moorej91 on 04 May 2007, 22:49:39
Have just read the faqs on the paperclip test, found it very informative. Will try test tomorrow. Thanks for info on the secondary pump, makes me feel better. Hope resetting with paper clip will sort out other problem.

Really impressed with all the help and knowledge on the forum.

Regards
Title: Re: Noise on startup, goes after 30 seconds
Post by: moorej91 on 05 May 2007, 12:57:54
Hi again,

Have just tried to do the paperclip test but it does not appear to be working. The eml warning light is not on at the moment, does it need to be lit before the test can be done? Have just taken the car out and it starts and drives fine. Could you tell me where the * and _ come on the dash, is it in the onboard computer screen or somewhere else.

Ta.
Title: Re: Noise on startup, goes after 30 seconds
Post by: moorej91 on 05 May 2007, 17:29:11
I have just driven 25 miles with no problem with no warning light showing, then the car cut out. The car started imediately but the warning light stayed on. When I got home I did the paper clip test. I have an omega estate 1999 2.0cd  automatic. I jumped pin numbers 5 and 6 as per faqs, and started the engine, the light stayed on and did not flash. I hen tried with ingnition on but engine not running. I did not get the *_** to start. As far as I can make out after looking for 3 sequences is

10 - 3 - 3 - 5

Does this mean anything as I cant find it in the fault code numbers? Am I doing the test right?

Many thanks agian for your help.
Title: Re: Noise on startup, goes after 30 seconds
Post by: Craig_R on 05 May 2007, 18:28:34
0335 Crank sensor  
Title: Re: Noise on startup, goes after 30 seconds
Post by: moorej91 on 05 May 2007, 19:20:48
Thankyou. I have just read up on a few more pages and found out that it did mean crank sensor. However on the same page it said that if the engine was not running it would give crank sensor fault also.

If I try to start the engine the light stays on but does not flash at all.
Title: Re: Noise on startup, goes after 30 seconds
Post by: TheBoy on 05 May 2007, 20:33:48
The 2.0l does not flash out codes if engine running, unlike V6.
Title: Re: Noise on startup, goes after 30 seconds
Post by: moorej91 on 05 May 2007, 21:37:52
Are you saying that it is the crank sensor is my problem? If this is the fault is it just a case of fitting a new crank sensor switch or is it or could it be a more serious problem?

Are they easy to fit?


Many thanks
Title: Re: Noise on startup, goes after 30 seconds
Post by: jack2uk on 05 May 2007, 22:21:37
Hi, Mine has done the same (2.5 V6 Estate) for 18 months, never been a problem, tends to be for a shorter time period when the engine is warm.