Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: Andy A on 04 January 2015, 11:09:04
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Omega 2.2 petrol manual 2003.
When the engine was at idle I had problems taking the oil filler cap off took and when I did get it off I found an excessive amount of air pressure coming out of the rocker cover. So much pressure that when I went to put the cap back on, it would rattle against the opening because of the excessive amount of air pressure pushing past from the cam cover.
I have already replaced all crankcase breather pipes with new and cleaned out throttle body etc, months ago. I did not have this problem back then.
The engine runs the same as it always has with the exception of only doing 17 mpg around town with the air con off. Way below where it should be for a manual 2,2 petrol.
It does not use any oil or lose any coolant.
Anyone know what might be the problem and what I need to do to fix it?
Thanks
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Omega 2.2 petrol manual 2003.
When the engine was at idle I had problems taking the oil filler cap off took and when I did get it off I found an excessive amount of air pressure coming out of the rocker cover. So much pressure that when I went to put the cap back on, it would rattle against the opening because of the excessive amount of air pressure pushing past from the cam cover.
I have already replaced all crankcase breather pipes with new and cleaned out throttle body etc, months ago. I did not have this problem back then.
The engine runs the same as it always has with the exception of only doing 17 mpg around town with the air con off. Way below where it should be for a manual 2,2 petrol.
It does not use any oil or lose any coolant.
Anyone know what might be the problem and what I need to do to fix it?
Thanks
Also forgot to mention that if I put my hand over the oil filler hole it makes a similar sound to putting my hand over the exhaust tail pipe. A puff, puff, puff sound with the amount of pressure pushing past the palm of my hand. If that makes any sense.
Thanks
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I'd be checking the breathers again.
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I'd be checking the breathers again.
Thanks for replying.
I took the three breather pipes off the cam cover and they are clean.
With the engine running I put my thumb over the small pipe from the cam cover that goes to the throttle body and that is sucking air nicely. So the hole in the throttle body is clear.
With the engine running I stuck a thumb over the large hole on the can cover where the breather pipe came off and there was plenty of air coming out of the small hole. I then blocked the small hole and there was plenty of air coming out from the large hole. So no blockage in the cam cover itself.
Is there any other pipes or valves that I need to check?
How much positive pressure should I have coming from the crankcase?
Thanks
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Is the oil level correct? Not over filled?
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Is the oil level correct? Not over filled?
Yes the oil level is correct, just below the max mark when cold.
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Metal pipe entering crankcase clear?
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Metal pipe entering crankcase clear?
If you mean the one at the back on the pass side that connects to the rubber hose from the cam cover and connects to the bottom crankcase then yes it is clear.
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Omega 2.2 petrol manual 2003.
When the engine was at idle I had problems taking the oil filler cap off took and when I did get it off I found an excessive amount of air pressure coming out of the rocker cover. So much pressure that when I went to put the cap back on, it would rattle against the opening because of the excessive amount of air pressure pushing past from the cam cover.
I have already replaced all crankcase breather pipes with new and cleaned out throttle body etc, months ago. I did not have this problem back then.
The engine runs the same as it always has with the exception of only doing 17 mpg around town with the air con off. Way below where it should be for a manual 2,2 petrol.
It does not use any oil or lose any coolant.
Anyone know what might be the problem and what I need to do to fix it?
Thanks
That is about normal :y And is the flexi pipe on the end of the metal crankcase breather pipe clear
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Omega 2.2 petrol manual 2003.
When the engine was at idle I had problems taking the oil filler cap off took and when I did get it off I found an excessive amount of air pressure coming out of the rocker cover. So much pressure that when I went to put the cap back on, it would rattle against the opening because of the excessive amount of air pressure pushing past from the cam cover.
I have already replaced all crankcase breather pipes with new and cleaned out throttle body etc, months ago. I did not have this problem back then.
The engine runs the same as it always has with the exception of only doing 17 mpg around town with the air con off. Way below where it should be for a manual 2,2 petrol.
It does not use any oil or lose any coolant.
Anyone know what might be the problem and what I need to do to fix it?
Thanks
That is about normal :y And is the flexi pipe on the end of the metal crankcase breather pipe clear
Yes all clear.
Could a blown head gasket cause this?
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Oil cap shouldnt rattle when engine is running,check black rubber seal is intact,or replace cap.
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Oil cap shouldnt rattle when engine is running,check black rubber seal is intact,or replace cap.
I was tying to point out that there was so much pressure that it rattled the cap as I was putting it back on. It was fine once fitted. Sorry for any confusion.
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Once warmed up, what is the temp gauge showing?
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Once warmed up, what is the temp gauge showing?
Just run the engine up to temperature and its around 92 deg max.
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Once warmed up, what is the temp gauge showing?
Just run the engine up to temperature and its around 92 deg max.
Ok, that sounds pretty normal... lazy thermostat and consequent cool running kills the fuel economy, but, that said with the lower temps lately... does the 2.2 have a separate ECU temp sensor?
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Once warmed up, what is the temp gauge showing?
Just run the engine up to temperature and its around 92 deg max.
Ok, that sounds pretty normal... lazy thermostat and consequent cool running kills the fuel economy, but, that said with the lower temps lately... does the 2.2 have a separate ECU temp sensor?
Not sure. How can I tell?
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does the 2.2 have a separate ECU temp sensor?
Yep
Not sure. How can I tell?
Rear of engine by EGR. One sensor for the dash gauge, t`other for coolant temp.
Rear of 2.0ltr in pic, 2.2 same minus the DISPACK
(http://images.omegaowners.com/images/guides/2.2_useful_pics/Tempsenders_resize.jpg)
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does the 2.2 have a separate ECU temp sensor?
Yep
Not sure. How can I tell?
Rear of engine by EGR. One sensor for the dash gauge, t`other for coolant temp.
Rear of 2.0ltr in pic, 2.2 same minus the DISPACK
(http://images.omegaowners.com/images/guides/2.2_useful_pics/Tempsenders_resize.jpg)
Nice one Rob. Do you know if "My Naff Code Reader" software will be able to tell me if the ECU temp gage is working correct?
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It should raise a code... P0115 iirc ;)
Won't solve the crankcase pressure, but might help the economy...
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It should raise a code... P0115 iirc ;)
Won't solve the crankcase pressure, but might help the economy...
Thanks Al, I'll borrow a laptop in the week and see what comes up.
Do you know how much crankcase pressure is acceptable if any?
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Can't help there :-[ There will always be some pressure, but a lot of variables once time and wear are factored in...
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Dodgy ECT sensor should illuminate the MIL Andy
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Mines about 18-19 round town so nowt to worry about and as petrols getting cheaper who cares ;D
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Mines about 18-19 round town so nowt to worry about and as petrols getting cheaper who cares ;D
Vlad. ;D
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Whats the mileage of the car and has it ever had a head gasket replaced :y
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Head gasket failing won't pressurise the crank case.
Is the cam timing OK?
Oil consumption up?
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Dodgy ECT sensor should illuminate the MIL Andy
No MIL light on.
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Whats the mileage of the car and has it ever had a head gasket replaced :y
The mileage is 115000 and I don't know if the head gasket has ever been done.
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Head gasket failing won't pressurise the crank case. Could you explain what will?
Is the cam timing OK? Checked the timing this morning and all is still aligned correctly.
Oil consumption up? No. It hasn't used any oil at all.
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Is there a PCV valve on my 2.2 petrol 2003 and where will I find it?
Thanks
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Head gasket failing won't pressurise the crank case. Could you explain what will?
Is the cam timing OK? Checked the timing this morning and all is still aligned correctly.
Oil consumption up? No. It hasn't used any oil at all.
The key thing that will pressurise the crank case is blow by gases, head gasket is very very very very unlikely to as the section around the fire rings is a coolant jacket hence you would see coolant loss and a very heavily pressurised cooling system.
There is no PCV valve, what I have seen though is crud in the top of the cam cover blocking the PCV ports.
Also be aware, is the hiss when you remove the oil filler gas escaping or air being sucked in as the crank case will run at a slight vaccum under normal operating conditions.
If you remove the large breather from the pre throttle connection and then blank the port it connected to on the inlet, run the engine do you get much flow from the breather tube?
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It should raise a code... P0115 iirc ;)
Only if frecked. Not if lazy or covered in k-seal etc
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It should raise a code... P0115 iirc ;)
Only if frecked. Not if lazy or covered in k-seal etc
Ok, so only conclusive test is Tech 2 reading compared to gauge reading :-\
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It should raise a code... P0115 iirc ;)
Only if frecked. Not if lazy or covered in k-seal etc
Ok, so only conclusive test is Tech 2 reading compared to gauge reading :-\
Live data is only true way. And comparing it with the Live data of the instrument panel, as the needle reading is, errr, "frigged".
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Gotcha ;)
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I'd be checking the breathers again.
Thanks for replying.
I took the three breather pipes off the cam cover and they are clean.
With the engine running I put my thumb over the small pipe from the cam cover that goes to the throttle body and that is sucking air nicely. So the hole in the throttle body is clear.
With the engine running I stuck a thumb over the large hole on the can cover where the breather pipe came off and there was plenty of air coming out of the small hole. I then blocked the small hole and there was plenty of air coming out from the large hole. So no blockage in the cam cover itself.
Is there any other pipes or valves that I need to check?
How much positive pressure should I have coming from the crankcase?
Thanks
The crankcase should always be under suction, so that noxious crankcase gases are sucked into the engine and burned. You say the cam cover is pressurised at idle, that is when the small hole taking high vacuum between throttle and engine provides suction. At high throttle openings there is little vacuum remaining at this point, so suction is taken between throttle and air filter through the large hose. You say you have checked the small pipe for suction at idle. You do not seem to have checked suction in the large pipe.
I have not got a 2.2 here, only a 2.0. That is very prone to blockage by oil of the small hole, which does the job at idle. This can be cleared by poking a wire through it. It may be your small hole is partially blocked, so that the suction is not sufficent to match pressure from blow past. That would result in pressurisation of cam cover at idle.
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Head gasket failing won't pressurise the crank case. Could you explain what will?
Is the cam timing OK? Checked the timing this morning and all is still aligned correctly.
Oil consumption up? No. It hasn't used any oil at all.
The key thing that will pressurise the crank case is blow by gases, head gasket is very very very very unlikely to as the section around the fire rings is a coolant jacket hence you would see coolant loss and a very heavily pressurised cooling system.
There is no PCV valve, what I have seen though is crud in the top of the cam cover blocking the PCV ports.
Also be aware, is the hiss when you remove the oil filler gas escaping or air being sucked in as the crank case will run at a slight vaccum under normal operating conditions. When I take the filler cap off I get a lot of positive air pressure escaping and no vaccum.
If you remove the large breather from the pre throttle connection and then blank the port it connected to on the inlet, run the engine do you get much flow from the breather tube? Yes, enough to feel the air pressure from 4-5 inches away from the end of the tube.
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I'd be checking the breathers again.
Thanks for replying.
I took the three breather pipes off the cam cover and they are clean.
With the engine running I put my thumb over the small pipe from the cam cover that goes to the throttle body and that is sucking air nicely. So the hole in the throttle body is clear.
With the engine running I stuck a thumb over the large hole on the can cover where the breather pipe came off and there was plenty of air coming out of the small hole. I then blocked the small hole and there was plenty of air coming out from the large hole. So no blockage in the cam cover itself.
Is there any other pipes or valves that I need to check?
How much positive pressure should I have coming from the crankcase?
Thanks
The crankcase should always be under suction, so that noxious crankcase gases are sucked into the engine and burned. You say the cam cover is pressurised at idle, that is when the small hole taking high vacuum between throttle and engine provides suction. At high throttle openings there is little vacuum remaining at this point, so suction is taken between throttle and air filter through the large hose. You say you have checked the small pipe for suction at idle. You do not seem to have checked suction in the large pipe.
I have not got a 2.2 here, only a 2.0. That is very prone to blockage by oil of the small hole, which does the job at idle. This can be cleared by poking a wire through it. It may be your small hole is partially blocked, so that the suction is not sufficent to match pressure from blow past. That would result in pressurisation of cam cover at idle.
I'll take the throttle body off and give it a good clean and see if that's the problem. Maybe its part blocked like you said.
If not, I will buy a true 100psi leak down tester. Do you know of any good compressors on the market for around £100 that will run at 100psi and will be good enough for some air tools for the car?
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Found the problem at last.
The small new rubber hose that goes to the throttle body was at fault. Although brand new and fitted less than a year ago had air line cracks in it on closer inspection. I took it back and got it replaced. They said it was probably old stock. :o
Fitted the new one and although I still get a lot of positive pressure coming from the oil filler cap opening when the cap is off. When the cap is fitted I now get a negative pressure (suction) through the large breather pipe that comes from the cam cover and connects to the air filter pipe, when the engine is idling (I did not have this before it was positive pressure). So the crankcase when sealed, is now under negative pressure at last as it should be.
Thanks all, for all your help. :y