I wasn't sure if this deserved a new thread or not and I am also not sure it should be in the General Discussion, but here goes.

From time to time I come across things I see on my 2.4L engine that surprise me because I can't really figure out either what they do or why they look the way they do.

My first question is: in the following pict what is the purpose of this tube? There is nothing attached to it and it has a slight flare on the end. It almost looks like a line was supposed to be attached but no it is just an open ended about 1/4" tube. If I put my thumb over it there is no suction or pressure when the engine is running.




My second question, and it is something that TX-HHR and I have been discussing but we can't come up with an answer so I thought I would include it also. Thanks TX for all of your responses, I appreciate the help.



The stock oil cap has what appears to be some kind of vent on the bottom and the cap, if you tap on it seems to be spring loaded. I was wondering since the Mobil 1 cap, although identical in all other ways is made like a more traditional oil cap, like I am used to seeing. I just wondered if there is something about the ECOTEC engine that requires pressure to be released.

If the moderators think this should be moved or merged with another thread that would be fine, but I couldn't see where else it might go because although it is about the 2.4L engine it is not about performance related issues.

Thanks John

 

Your first picture has something to do with a timing probe (if I remember correctly). Although the timing is controlled by the computer it can still be checked by some kind of probe. The stock cap is spring loaded to assist in releiving crankcase pressure in the event of a malfunction of the PCV system instead of creating a leaky gasket, the little orifice looking thing is there to allow the release of pressure without the loss of engine oil.

 

No there isn't any specific book on this stuff, but I've been a hot rodder and engine builder for over 30 years. Although I'll be the first to admit that most of my expeience is with older non-computer controlled cars and most of what I learn about these new vehicles comes from kids that are now the new "Hot Rodders" and understand this new technology. Basic engine stuff has and probably never will change (with exception to rotaries and turbines), but the typical internal combustion engine (piston driven) will always be the same (on basics). So I trade this knowledge with others who are more current with the high tech stuff just to try to keep my head above the water level...LOL

The ECOTEC is still a basic engine, it's just equipped with several newer technology stuff, heck something as simple as the oil caps just takes a few minutes of study to figure out, but then again, you made me look. This also taught me something, so your not only someone who is curious....your also a teacher. What I'm saying is that this isn't something I even noticed, but in close examination I realized quickly what the purpose of the spring loaded cap is supposed to do and why, as well as the small orifice. I was only able to come to this conclusion because of my many years of experience with engines. Heck, I could be wrong....but I doubt it. And as far as the tube thingy you shot a picture of, that's a carry over from when car's first went from electronic controls to computer controls.

Your best bet to get to get current info on modern engines is right where you are. Mike (from SoCalHHR's) is a great source of info, many others can give you tons of info as well. Everyone here can contribute their knowledge, experiences, trials and errors to your quest for knowledge. -Dan

 

Dan-D,

That's interesting the stock oil cap cap can vent presure. I have to say when I looked mine over it just appeared to be a two piece unit that snaped together, but I'm no mechanic. This makes me wonder, how often does the PCV get so clogged that it would cause a venting problem? Once, or twice over the life of the motor? What is the maintence schedule on the PCV and where is the PCV valve on the ECOs?

John11, see what you started here...

 

TX

I laughed out load when I read your last line. I think what I started is a good thing, and I know by your posts you do too That is why I joined this form to discuss things with people who are asking the same questions. Thanks for your contributions.

And Dan-d
Thank You for explaining about your learning curve, and thaks for the compliment, as a matter of fact, I am a teacher. I teach architecture at the University here in Charlotte, UNC Charlotte. Classes start tomorrow
Thanks again

 

I get it...Architecture professor OK....give me a week and I'll build a model of the oil cap and make some presentation drawings to explain how it fits in the context of the engine bay by making a statement yet not overpowering it's surroundings. and since this is class I assume no budget restraints.


I miss being able to design without budget limitations...

 

TX

You remember
Actually I am a professor, but I teach our 4thYr/Graduate Design Build Studio so budget is an issue. Here is the link to our website if interested.
http://www.coa.uncc.edu/gallery/main.php?g2_itemId=983

 

No offense, you will think your an idiot after i tell you this, but that little tube with the flared end, holds a plastic engine cover, particularily on the cobalts, they just didnt change over the the covers to the HHR's. There is no such thing as a timing probe, nor can it be changed unless its done electronically to change things such as ignition timing, or you can change cam gears, which advances or retards cam timing. Sorry to give you the bad news buddy, but thats the truth.

 

Great web site John!

 

dnbguy89

Man I should have looked at that little tube more closley. It connects to nothing except a bracket and is actually only about 2 inches long. It just seemed like a funny shape, like a flared gas line, but your right it looks like it was just left over and never removed. Since I put my CGS on I can see a lot more things on the engine. Thanks for the input.