Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: ARH1 on 04 July 2009, 21:31:55

Title: whistling engine
Post by: ARH1 on 04 July 2009, 21:31:55
Hi Guys and Gals,
My engine on the 2.5 v6 0mega estate is playing up, Firstly the revs have dropped from approx 550 to around 490 and appears a bit rumbley at idle (no knocks though). Secondly there is what appears to be a tappet noise on idle (sounds like all tappets not just one. sewing machine like noise lol)(worse on start up from cold and still audible when warmed up) thirdly, at idle or changing gears a loud whistle is coming from the engine (around the plenum area). engine starts and runs fine but wary of these engines due to bad reports. oil and water fine although fan comes on on short journeys and at idle (switches off when temp back to normal) Slight smoke from rear exhaust even when warm.cant tell if white or blue or both(not excessive) oil consumption appears normal and no water loss
Car has done 112k miles
Have replaced cam covers 2000 mls ago
have replaced oil twice in 3000 miles (was black when I got car)   cambelt reportedto have benn changed at 98 k. any ideas? is eng ready to decease? or could it be a gasket in the inlet side and a possible treament to the lifters to cure?
Thanx guys
Title: Re: whistling engine
Post by: Ghost on 04 July 2009, 21:51:31
Have a look if you have any air leeks or that the plenum is fitted correctly.
Title: Re: whistling engine
Post by: Lizzie_Zoom on 04 July 2009, 22:05:39
Quote
Hi Guys and Gals,
My engine on the 2.5 v6 0mega estate is playing up, Firstly the revs have dropped from approx 550 to around 490 and appears a bit rumbley at idle (no knocks though). Secondly there is what appears to be a tappet noise on idle (sounds like all tappets not just one. sewing machine like noise lol)(worse on start up from cold and still audible when warmed up) thirdly, at idle or changing gears a loud whistle is coming from the engine (around the plenum area). engine starts and runs fine but wary of these engines due to bad reports. oil and water fine although fan comes on on short journeys and at idle (switches off when temp back to normal) Slight smoke from rear exhaust even when warm.cant tell if white or blue or both(not excessive) oil consumption appears normal and no water loss
Car has done 112k miles
Have replaced cam covers 2000 mls ago
have replaced oil twice in 3000 miles (was black when I got car)   cambelt reportedto have benn changed at 98 k. any ideas? is eng ready to decease? or could it be a gasket in the inlet side and a possible treament to the lifters to cure?
Thanx guys

When you did the cam covers did you replace the 'O' rings (x6) of the intake to the plenum?  It could well be you have an air leak around one or more of them. ;) ;)

Title: Re: whistling engine
Post by: RossMk2 on 04 July 2009, 22:53:46
As i spend more and more time on this website, more threads pop up by people that my engine seems to have wrong with it also! LOL I have the whistling plenium also but i replaced the o-rings on the intake manifold last time it was off.

Also with the intake being spun around the 4 breathers that come from the plenium have been blocked off, what does the black plastic thing on top actually do? Im thinking of  removing it completely and blocking the whole if its doing nothing for me but the whistle doesnt seem to be coming from the top of the plenium.
Title: Re: whistling engine
Post by: feeutfo on 05 July 2009, 04:18:19
Quote
As i spend more and more time on this website, more threads pop up by people that my engine seems to have wrong with it also! LOL I have the whistling plenium also but i replaced the o-rings on the intake manifold last time it was off.

Also with the intake being spun around the 4 breathers that come from the plenium have been blocked off, what does the black plastic thing on top actually do? Im thinking of  removing it completely and blocking the whole if its doing nothing for me but the whistle doesnt seem to be coming from the top of the plenium.

What do you mean "spun around"? Eco tech bit is breathers. 2 small holes to plenum. Must be clear and connected or youll blow cam cover seals. It vents crank case pressure.

My old cdx used to whistle. It was secondary air injection related on mine. But was obviously not coming from plenum area.

 If def intake then also check seals under black plastic inlet and injector manifold.
Edit.
Ah Astra v6. That explanes it.
Title: Re: whistling engine
Post by: ARH1 on 05 July 2009, 11:02:56
Many thanx for your replies. 6 plenumn chamber seals replaced when cover gaskets replaced. I wonder if I maybe caught one on refitting. I will get another set and replace just to be sure. Would this cause the sewing machine type rattle from the lifters though if it was drawing air? I have heard there is a special  oil additive for the lifters does anybody know what it is?
ARH1
Title: Re: whistling engine
Post by: Lizzie_Zoom on 05 July 2009, 12:39:11
Quote
Quote
As i spend more and more time on this website, more threads pop up by people that my engine seems to have wrong with it also! LOL I have the whistling plenium also but i replaced the o-rings on the intake manifold last time it was off.

Also with the intake being spun around the 4 breathers that come from the plenium have been blocked off, what does the black plastic thing on top actually do? Im thinking of  removing it completely and blocking the whole if its doing nothing for me but the whistle doesnt seem to be coming from the top of the plenium.

What do you mean "spun around"? Eco tech bit is breathers. 2 small holes to plenum. Must be clear and connected or youll blow cam cover seals. It vents crank case pressure.

My old cdx used to whistle. It was secondary air injection related on mine. But was obviously not coming from plenum area.

 If def intake then also check seals under black plastic inlet and injector manifold.
Edit.
Ah Astra v6. That explanes it.


Chris is absolutely right and the last thing you want to do is block off the breather system! :o :o :o :o :o :o   The designers put that all there for a reason, which is to let your engine crank case breath ;).  Block it all up at your peril! :-X :-X :-X :-X :-X :-X

Title: Re: whistling engine
Post by: RossMk2 on 05 July 2009, 14:56:09
I will have to post a picture up to explain, only thing that is blocked up is the EGR valve and the 4 exits from the top of the plenium, this being that the intake has been spun 180deg to fit into the astra and have the electrics against the bulkhead.