Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: Paul M on 11 January 2007, 15:34:38
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I'm getting a sort of buzzing noise on startup that sounds like an electric motor with failing bearings. After reading posts on here I'm suspecting the secondary air injection pump (the one in the front nearside wing) so I want to disconnect it to check. Is there any way of doing so without having to get into the wheel arch? I was thinking maybe a fuse can be removed, hopefully without disabling anything else that may be important.
The noise has been there since I bought the car, I just never spent much time investigating it as it's reasonably subtle (especially with my crappy exhaust!) and it goes away reasonably quickly. Strangely though it seems to change frequency if I rev the engine, does this sound normal for a secondary air pump?
Cheers.
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Look under bumper on that side - you can see the connector ;)
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From underneath the car? I did have a look there last week, and could see the big cylinder thing in front of the wheel I assume is the pump, but not the connector. Will have a better look this weekend in the daylight and with that side of the car raised.
Cheers.
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From underneath the car? I did have a look there last week, and could see the big cylinder thing in front of the wheel I assume is the pump, but not the connector. Will have a better look this weekend in the daylight and with that side of the car raised.
Cheers.
Thats the area to look in.
I bet Markjay has a picture.... :P
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I'm getting a sort of buzzing noise on startup that sounds like an electric motor with failing bearings. After reading posts on here I'm suspecting the secondary air injection pump (the one in the front nearside wing) so I want to disconnect it to check. Is there any way of doing so without having to get into the wheel arch? I was thinking maybe a fuse can be removed, hopefully without disabling anything else that may be important.
The noise has been there since I bought the car, I just never spent much time investigating it as it's reasonably subtle (especially with my crappy exhaust!) and it goes away reasonably quickly. Strangely though it seems to change frequency if I rev the engine, does this sound normal for a secondary air pump?
Cheers.
My Omega has also done this from time to time since I got it over a year ago - doesn't appear to be causing any problems, and as you say, it goes away after the engines warmed up.
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Cheers guys, I'll have a look at the weekend, it's too dark in the evenings.
It doesn't cause me any problems either, but if I can easily fix it then I will as it's a bit of an annoyance. Even more so if I get a decent exhaust meaning the car should be near silent at idle.
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There is a fuse in the engine bay fuse box that just supplies the secondary air pump. I think it's the orange 30A one.
There is also a relay that just controls the SAP. Pull either of these - dead easy.
The reason the noise changes with the revs is the battery voltage changes a little too.
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Hopefully some better info.
The fuse is here (F5 in red):
(http://i83.photobucket.com/albums/j292/jasonhanlon/SAPfuse.jpg)
Plus, from the Haynes wiring diagrams:
Fuse F49, 50Amp is the fuse that supplies the SAP (and nothing else)
Relay K12 switches the power (and nothing else)
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Nice one I'll try pulling the fuse, that being the easiest way to try :)
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I know this may sound a stupid question but do you actually need the secondary airpump?
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I know this may sound a stupid question but do you actually need the secondary airpump?
No.
You can remove the pump and pipework.
Remove the metal pipe etc that runs across the cambelt cover, disconnect it at the 2" rubber joiner pipes where it connects to the exhaust manifold pipes. Use a piece of 1/2" steel or alloy rod to blank off the pipes to the exhaust manifolds.
You can remove the vacuum operated switch-off valve but you must re-fit the vacuum solenoid to the electrical connector else the eml will light. The solenoid ty-raps neatly to the radiator fan bracket.
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I know this may sound a stupid question but do you actually need the secondary airpump?
No.
You can remove the pump and pipework.
Remove the metal pipe etc that runs across the cambelt cover, disconnect it at the 2" rubber joiner pipes where it connects to the exhaust manifold pipes. Use a piece of 1/2" steel or alloy rod to blank off the pipes to the exhaust manifolds.
You can remove the vacuum operated switch-off valve but you must re-fit the vacuum solenoid to the electrical connector else the eml will light. The solenoid ty-raps neatly to the radiator fan bracket.
Forgive my ignorance guys, but if you don't need it why would they bother fitting one in the first place? :-?
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It reduces emissions at start up (when rich mixtures cause a lot of partially burnt crap like CO) by injecting air into the exhaust manifolds, the heat and excess oxygen allow some of the gases to combine with oxygen (CO -> CO2), both reducing noxious gases and producing extra heat in the process which speeds warm up of the cats.
After a few minutes it's no longer needed as the engine has started to warm, so it's switched off.
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It reduces emissions at start up (when rich mixtures cause a lot of partially burnt crap like CO) by injecting air into the exhaust manifolds, the heat and excess oxygen allow some of the gases to combine with oxygen (CO -> CO2), both reducing noxious gases and producing extra heat in the process which speeds warm up of the cats.
After a few minutes it's no longer needed as the engine has started to warm, so it's switched off.
Thanks for educating me on that one Paul. :y
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Hopefully some better info.
The fuse is here (F5 in red):
(http://i83.photobucket.com/albums/j292/jasonhanlon/SAPfuse.jpg)
Plus, from the Haynes wiring diagrams:
Fuse F49, 50Amp is the fuse that supplies the SAP (and nothing else)
Relay K12 switches the power (and nothing else)
I removed the fuse, although it's a 30 A in mine and the fuse box layout is a little different, but it hasn't made any difference. So either it's something else making the noise, or that fuse doesn't control the air injection pump in my car. Nothing else seemed to be disabled though so I wonder what it does if not the pump. I may try the relay too, but I'm beginning to suspect it may be something else making the noise >:(
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I get a similar sound from mine about ten seconds after I start it up, sounds like a pump or compressor, and runs for about five seconds - is that what you get? I seem to remember reading somewhere on this forum (or the other one) that it's the coolant pump running to prime the heater system.
Dominic
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No, it lasts a bit longer on mine and also it starts as soon as the engine is started from cold.
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Paul M, unplug the pump to see if it is that making noise...
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The secondary air pumps runs for a few seconds to a few minutes depending on how cold the engine is when it's started.
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Will disconnect the plug when I get a chance, probably the weekend again.
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Mine makes that noise too - just ignore it and tell the neighbours its the supercharger :y
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Do they all have one of these?
I had a V6 Vectra which defiantly had one, very loud on start-up.
Can't say I’ve noticed one on mine, although its only a 4 pot
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Isn't there a compressor for the self-levelling rear suspension under the wheel arches too? Maybe it's that.
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Isn't there a compressor for the self-levelling rear suspension under the wheel arches too? Maybe it's that.
Only on the posher models ;), and it will be drivers side...
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Funnily enough mine has self levelling suspension ::)
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Funnily enough mine has self levelling suspension ::)
Rare on an MV6, but MV6 (prefacelift) would fit into my description of "posher model" ;D
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:D yeah I was rather surprised when it was in getting the tracking done, and the guy mentioned the self levelling suspension. I was a bit sceptical until he pointed out the vacuum pipes going into the dampers ::)
Not that I'm ever likely to use it, never carry anything heavy. Although I guess maybe the dual-fuel tank may be considered heavy lol... wonder if it makes any difference there?
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Disconnected the pump... no change :( So it's not that making the noise, I've reconnected it again.
TBH I was a little sceptical as this noise seems to rise and fall with the revs, although I'm at a loss as to what it can be seeing that it only happens at cold :-/ It's like a "brrrrrrr" kind of noise if that's any help ;D
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Sorry for raving this from the grave - but I also get this noise at start up - did you ever find out what it was? (there I was reading through this old thread thinking "any minute now I'll reach the answer", and the thread just stopped! I can't go to bed not knowing, its like reading a good book then finding out that the last page has been torn out and you can't find out who dunnit! :)
Pat
Omega Hypochondriac
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I suspect it wasn't the pump that got disconnected......probably one of the horns...its a common mistake (done it myself!).....it will be the airpump.....try it!
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...I bet Markjay has a picture.... :P
Sorry I did not get here earlier... prob too late now anyway ;D
(http://img255.imageshack.us/img255/4356/secondaryairpumpcb9.jpg) (http://imageshack.us)