Dipstick Popping Out
12-14-2008, 05:05 PM
#51
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https://www.cobaltss.net/forums/show...p+stick+poping
thats the only thread i could find with info for you...
thats the only thread i could find with info for you...
12-14-2008, 05:16 PM
#52
Senior Member
Two things that have been mentioned would be the first things I'd look into. First is to check the entire positive crankcase ventilation (PCV) system and ensure it is working correctly and nothing is pinched (hoses) or damaged/clogged (PCV valve). The job of the PCV system is to alleviate pressure that builds up in the lower end up the crankcase, which is normally caused by "blowby" or pressurized compression gasses leaking down from the combustion chamber past the piston rings. If the pressure gets too high you can have issues like you're seeing with the dip stick being pushed out, oil being pushed into the PCV system, or even seals being pushed out and leaking.
Most cars relieve this pressure by placing a PCV valve, a one-way check valve, between the valve cover and intake tract (usually to/near the throttle body). The valve is placed here because the top end of the head under the valve cover is linked to the crankcase on the lower end of the engine via the oil drain-back passages for the valvetrain. The valve is a one-way design so pressure and vapors can be released to the intake tract and burned but closes off during a backfire or when the engine is not running to trap vapors from being released (so they don't leak out into the atmosphere). On many forced induction cars the valve also allows the engine to suck the blowby vapors into the intake tract when under light load cruising when the engine is creating vacuum in the intake tract and then seal off when under boost so pressure created by the blower/turbo doesn't get forced back into the crankcase.
There is also normally a fresh air inlet hose that has a breather filter on the end and is usually integral to the air intake box. If this gets clogged or is too small the PCV system can't vent the engine properly. These stock systems vent to/from the intake tract to include the air box and near the throttle body and don't just have a simple breather filter on both ends that vent to the atmosphere (like on many older V8 cars, etc.) due to emission reasons. The manufacturer can't let fuel and other oil vapors vent out and must instead send them through the engine to be burnt.
If the system checks out and you replace the PCV valve (which is probably a good idea if you've got more than a few miles on the car) and you still have the problem you'd then want to perform a leak-down test. It's different than a compression tester and you'll need access to an air compressor. Basically a compression tester has you install it into the spark plug hole in the head, open the throttle body, then crank the engine without letting it start. The compression tester has a one-way valve that allows the gauge to record the peak pressure spikes on the compression stroke of the engine.
The leak-down tester works a little differently. It also installs into the spark plug hole but doesn't rely on the engine cranking over to build pressure in the cylinder's combustion chamber. Instead you rotate the engine over by hand until both intake and exhaust valves are closed and then apply regulated pressure from an air compressor (normally ~70-80 psi for many testers). The tester has a gauge and when you shut off the pressure valve from the air supply you watch and see how long it takes for the pressure to bleed down. If it drops fast, for example, you could have an issue with the valve seats or the piston rings not sealing or possibly a head gasket leak (not as likely with the newer multi-layer steel head gaskets which usually seal or completely fail).
The factory service manual should outline the procedures and acceptable specifications or recommend using the gauge's instruction manual and procedures. If the leak-down test comes back successful and the PCV system is working correctly I'd then check the valve guides and seals for wear and leaks. That's another way for pressurized air to escape from the intake or exhaust ports and up into the top end of the engine under the valve cover (and therefore also pressurize the crankcase as well).
If the engine is in good health more than likely it's something in the PCV system. If you understand the purpose of the PCV system but not the specific setup on your car try taking a good look at your under hood emissions label for the vacuum line layout then trace where those lines are physically located.
Most cars relieve this pressure by placing a PCV valve, a one-way check valve, between the valve cover and intake tract (usually to/near the throttle body). The valve is placed here because the top end of the head under the valve cover is linked to the crankcase on the lower end of the engine via the oil drain-back passages for the valvetrain. The valve is a one-way design so pressure and vapors can be released to the intake tract and burned but closes off during a backfire or when the engine is not running to trap vapors from being released (so they don't leak out into the atmosphere). On many forced induction cars the valve also allows the engine to suck the blowby vapors into the intake tract when under light load cruising when the engine is creating vacuum in the intake tract and then seal off when under boost so pressure created by the blower/turbo doesn't get forced back into the crankcase.
There is also normally a fresh air inlet hose that has a breather filter on the end and is usually integral to the air intake box. If this gets clogged or is too small the PCV system can't vent the engine properly. These stock systems vent to/from the intake tract to include the air box and near the throttle body and don't just have a simple breather filter on both ends that vent to the atmosphere (like on many older V8 cars, etc.) due to emission reasons. The manufacturer can't let fuel and other oil vapors vent out and must instead send them through the engine to be burnt.
If the system checks out and you replace the PCV valve (which is probably a good idea if you've got more than a few miles on the car) and you still have the problem you'd then want to perform a leak-down test. It's different than a compression tester and you'll need access to an air compressor. Basically a compression tester has you install it into the spark plug hole in the head, open the throttle body, then crank the engine without letting it start. The compression tester has a one-way valve that allows the gauge to record the peak pressure spikes on the compression stroke of the engine.
The leak-down tester works a little differently. It also installs into the spark plug hole but doesn't rely on the engine cranking over to build pressure in the cylinder's combustion chamber. Instead you rotate the engine over by hand until both intake and exhaust valves are closed and then apply regulated pressure from an air compressor (normally ~70-80 psi for many testers). The tester has a gauge and when you shut off the pressure valve from the air supply you watch and see how long it takes for the pressure to bleed down. If it drops fast, for example, you could have an issue with the valve seats or the piston rings not sealing or possibly a head gasket leak (not as likely with the newer multi-layer steel head gaskets which usually seal or completely fail).
The factory service manual should outline the procedures and acceptable specifications or recommend using the gauge's instruction manual and procedures. If the leak-down test comes back successful and the PCV system is working correctly I'd then check the valve guides and seals for wear and leaks. That's another way for pressurized air to escape from the intake or exhaust ports and up into the top end of the engine under the valve cover (and therefore also pressurize the crankcase as well).
If the engine is in good health more than likely it's something in the PCV system. If you understand the purpose of the PCV system but not the specific setup on your car try taking a good look at your under hood emissions label for the vacuum line layout then trace where those lines are physically located.
Last edited by blackbird; 12-14-2008 at 05:22 PM. Reason: speeling and gramore errores
12-14-2008, 06:23 PM
#56
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pull the oil cap. see smoke, you have problems. excessive pressure. you have problems. a leak down would be a good thing to try.
putting a breather filter on the valve cover and/or an oil cap replacement will do the exact same thing. the oil cap actually breathes better.
what codes are you throwing, and did you possibly put the gasket on backwards?
cracked head
dead piston
clogged pcv
gasket on backwards
putting a breather filter on the valve cover and/or an oil cap replacement will do the exact same thing. the oil cap actually breathes better.
what codes are you throwing, and did you possibly put the gasket on backwards?
cracked head
dead piston
clogged pcv
gasket on backwards
12-14-2008, 10:22 PM
#58
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pull the oil cap. see smoke, you have problems. excessive pressure. you have problems. a leak down would be a good thing to try.
putting a breather filter on the valve cover and/or an oil cap replacement will do the exact same thing. the oil cap actually breathes better.
what codes are you throwing, and did you possibly put the gasket on backwards?
cracked head
dead piston
clogged pcv
gasket on backwards
putting a breather filter on the valve cover and/or an oil cap replacement will do the exact same thing. the oil cap actually breathes better.
what codes are you throwing, and did you possibly put the gasket on backwards?
cracked head
dead piston
clogged pcv
gasket on backwards
12-14-2008, 10:35 PM
#59
Banned
Thread Starter
pull the oil cap. see smoke, you have problems. excessive pressure. you have problems. a leak down would be a good thing to try.
putting a breather filter on the valve cover and/or an oil cap replacement will do the exact same thing. the oil cap actually breathes better.
what codes are you throwing, and did you possibly put the gasket on backwards?
cracked head
dead piston
clogged pcv
gasket on backwards
putting a breather filter on the valve cover and/or an oil cap replacement will do the exact same thing. the oil cap actually breathes better.
what codes are you throwing, and did you possibly put the gasket on backwards?
cracked head
dead piston
clogged pcv
gasket on backwards
PCV seems like its working I felt the air sucking in.
When I pulled my manifold gasket that mates the intake manifold to
the head, I had a lot of gunk build up. That gasket is the only thing I havn't checked since the popping dipstick...
still have a lot to learn on HPT.
Which tab do I go to view codes thrown on my vehicle?
12-14-2008, 11:42 PM
#61
Haz l33t wheelz.
Compression test was 170/172/176/174, somewhere in that ball park.
PCV seems like its working I felt the air sucking in.
When I pulled my manifold gasket that mates the intake manifold to
the head, I had a lot of gunk build up. That gasket is the only thing I havn't checked since the popping dipstick...
still have a lot to learn on HPT.
Which tab do I go to view codes thrown on my vehicle?
PCV seems like its working I felt the air sucking in.
When I pulled my manifold gasket that mates the intake manifold to
the head, I had a lot of gunk build up. That gasket is the only thing I havn't checked since the popping dipstick...
still have a lot to learn on HPT.
Which tab do I go to view codes thrown on my vehicle?
12-15-2008, 12:00 AM
#64
Banned
Thread Starter
nah, methwouldnt do that...
i think the gasket went... there was some gunk build up in the two random holes in the head.
considering there was a bulletin for this gasket.... and its the last thing i havnt checked before opening up the motor. I'm willing to bet its the issue.
Last edited by Steven Flit; 12-20-2008 at 02:20 AM.
12-15-2008, 12:03 AM
#65
Haz l33t wheelz.
yeah, lets hope its just the gasket.
as far as meth goes, the cheaper forms of windsheild washer fluid have crappy powder dye that if not dissolved all the way, will cause buildup like that. just throwing that out there. learned it from someone else, passing it along.
as far as meth goes, the cheaper forms of windsheild washer fluid have crappy powder dye that if not dissolved all the way, will cause buildup like that. just throwing that out there. learned it from someone else, passing it along.
12-15-2008, 12:15 AM
#66
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mix ti 50/50 w/ distilled water
12-15-2008, 12:26 AM
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well tis what ive have told him.. im over at his house.. and it's either goona be the intake mani gasket.. or a head gasket.. tis all that's left.. but one question.. it kinda smell's like oil. not seein any smoke.. gonna pull the cap with it running.. see if there is smoke or not..
12-15-2008, 12:51 AM
#69
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12-15-2008, 12:53 AM
#71
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12-15-2008, 03:08 AM
#72
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yeah i smelt alot of oil burning with mine too. but no worries i highly doubt its a head gasket. 99% sure its your intake mani gasket. you could have went to the local dealer and got it too. takes about hour to 1 1/2 hrs to replace no biggie i have done 3 of em for sure. whats your compression like in all cylinders? (i know you checked it but i would like numbers please)
12-15-2008, 03:16 AM
#73
Banned
Thread Starter
yeah i smelt alot of oil burning with mine too. but no worries i highly doubt its a head gasket. 99% sure its your intake mani gasket. you could have went to the local dealer and got it too. takes about hour to 1 1/2 hrs to replace no biggie i have done 3 of em for sure. whats your compression like in all cylinders? (i know you checked it but i would like numbers please)