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How to fix your oil cap from leaking [Merged 3-8] leak leaky

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underdogTSI

20+ Year Contributor
33
0
Nov 16, 2002
Buffalo_NY
OK, my oil cap seems to leak, and when I take it off with the motor running, it shoots alot of air out, I also had that dip stick problem where it always pops out. I have bent the dip stick tube enough to keep it in there and put in a new pvc but nothing has stopped this...Anybody have this problem or solution?? Thanks.
 
I know this thread is old but I have the same problem, and it's really freakin annoying to lose synthetic oil this way.

I changed my cap, and I'm using TWO oem gaskets and it STILL leaks. I tried tightening the clips via the screw but that did nothing.

Any ideas on what can be done?
 
Are you seeing the oil on the top of the rocker cover by the cap?
There are other ways for it to get into the spark plug well that have nothing to do with the cap leaking.
And even more ways for the oil to vanish without pooling anywhere on the rocker cover.
 
The O-rings on the dipstick get hard and don't do their job.
Get some that will fit in the grooves on the shaft and fit tight in the metal sleeve for the stick.
Did this at the beginning of last summer and never blew my dipstick out yet.
Hope this helps
 
i wanted to add my experience to the flying dipstick/ leaking oil-cap phenomenon. I replaced my oil cap, added a second gasket and it was still leaking... a lot with flying dipstick. So i did a compression test and it wasn't good. Did a leak down test to check if it was the rings or valve train. In my case it was the valves. sometime in the past the timing belt had broke and a chunk of an intake valve was missing. The excessive blow by was blowing all kinds of oil out of the engine. Once fixed (valve job thanks Dan's cylinder head in Portland! they are awesome) but still oil showing up in the spark plug well. This is when i learned the valve cover gasket is notorious for cracking and leaking oil too. i had torqued mine on improperly and didn't use gasket sealant. when it leaked, i tightened it further and cracked it around the timing side. So... long story short:

  • check compression/leak down test - no sense arranging deck chairs on the Titanic.
  • Check oil cap gasket - make sure it seals tightly on the valve cover - add additional gasket if necessary
  • check for valve cover leaks/cracks - if so remove/replace valve cover, get a good gasket and sealant, only torque bolts to 3-5 ft/lb and make sure its even!
Hope someone can learn from my stubbornness!
 
I have a solid amount spraying out of the oil cap. Compression is 155 across the board. Oil cap + new gasket, have not doubled up gaskets. I need to replace the O ring gaskets as oil is getting into 2 of the wells but that is just recently and besides the point of the air pressure that is forcing all of this oil out of the cap. The friendly pool of oil in my valve cover has only recently come from my new tune, mainly when I did 272's and raised the rev limit and boost. I read around on tuners and trusted other people's experiences that I can wind my stock springs to 7.5-8k. Since I have good compression, I am trying to understand how this could be happening. I also was thinking that I have to be valve floating and with the float, air pressure is passing by up top under load pushing it out.. if I am understanding that concept correctly. It makes sense since this has only happened since I've been winding it out higher. I tried lowering the boost and shifting at 6.5k to see if I have any pooling, no oil coming out. 125k Miles on OEM springs as I doubt they have ever been replaced. I am about to order either Manley/Kiggly set of springs and retainers because I should have in the first place regardless, revised lifters and valve stem seals because I've also started having a little smoking from this issue. If that doesn't work then could it somehow be that my OEM valves are not sealing properly?
 
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Your valve guides could be worn allowing it to get up through them but if they ARE worn and wiggly then the new seals won't last long so I hope it isn't that, but thought I would throw it out there and you can check. Especially the exhaust guides.
 
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