New valve cover peep hole leak? Blow-by?

Cougar232 · Dec 30, 2005

I ust got a new nice red valve cover and a full gasket set for my 91 talon tsi. Now with the new gaskets and cover im getting like a half quart of oil laying in the valve cover after motor has been under a load. Also when I left off the throttle under boost i see smoke come out from under the car? I think its getting on the manifold not just outta the exhaust tip. I have replaced the pcv valve before but dont trust it. I have done alot of other wor to the engine, just upset that I replaced a carcked cover, and put on new gaskets and new stainless bolts and now I have more oil leaking than ever. Also should I leave the breather filter on?, it looks soaked.

NitrousPete · Dec 30, 2005

That could be the problem, if the breather filter is soaked it won't be able to vent. That could be forcing oil out of the vent hole. Also, double check the PCV valve, might as well just replace it being as inexpensive as they are.

iowaboostin · Dec 30, 2005

It's a pretty obvious thing but I'll throw it out there anyway. Is the breather filter facing the right way? If that or a new PCV won't fix it, I'd check again for a crack in the valve cover.

oldman · Dec 30, 2005

It's definitely an excessive crankcase pressure issue, the cause can be one or combination of the following.

1. Problems with crankcase ventilation capacity like Pete mentioned.

2. Excessive blow by from piston rings, a dry and wet compression test will help reveal this.

3. boost pressure leaking into crankcase via a stucked open pcv or worn vavle seals/ guides, a boost leak test with the oil cap open will help verify this.

I'm surprised that your dipstick didn't pop first before everything else, is the dipstick tube piched shut some how?

Cougar232 · Dec 31, 2005

I bought the car and at first with the old dipstick it would pop out, my new one is in very hard so thats why I dont come out I think. Also they car did smoke bluish white kinda when I would sit at a light for some time or a drivethru. On the highway it doesent like to maintain 65-70 mph at 3K rpms the turbo will sneak up at that speed under very little throttle and spool up and the car will buck and black smoke pours out the exhaust. Car still has power to about 5 and feels ok when your pushing it. I did remove the balance shaft in the rear since the bearing for it fell out and I removed the balance shaft belt. New front case and oil pump is also on the car and I have realy good oil pressure unless it gets real hot then it hits that first line on the gauge. All new gaskets are on the bottom end. I do have a compression tester and I wil try a wet/dry on all fur cylinders and post it. I do have valve seals in my gasket kit, but if the rings are shot then its over my head. Any other tips for reducing blowby or vent the valve cover better would be appreciated.

oldman · Dec 31, 2005

Go through the boost leak test (pcv and valve seals) and compression test as well as pulling the intake pipe and licp to check for signs of turbo shaft play and oil leakage. Try and pin point the problem first, it can very well be a simple defective pcv if you're lucky. Once you're able to get a better gauge of what the problem is, we can then talk about solutions.

Cougar232 · Jan 3, 2006

Ok, did the compression test today as per instructions.
Cylinder #1 -135
Cylinder #1w/oil-155

Cylinder #2 -125
Cylinder #2w/oil-150

Cylinder #3-150
Cylinder #3w/oil-170

Cylinder #4-150
Cylinder #4w/oil -165

These are my numbers, I need to figure out If I need new piston rings, head gasket or valve seals. Car does smoke blue at idle sometimes, did not get to check the turbo yet for shaft play. Lower intercooler pipe no oil in it. Oil is leaking from new front case near the crank and the valve cover sprays it out I believe threw the peep hole. Let me now what you think. I highly appreciate your input.

DSMLIFESTYLE · Jan 3, 2006

I'd check the valve cover itself for cracks and insure that you installed the gasket correctly,also fab up a cheap catch can out of a see-thur fram fuel filter along with the steps that the guys had came up with for you.

Tenacious-B · Jan 3, 2006

Sounds like your issue is rings at least with regard to the compression numbers. Did you replace the PCV, clean the breather, and perform the boost leak test yet?

Cougar232 · Jan 4, 2006

Could the boost getting past the rings cause my front case/oil pump/ gasket and seals to leak under the pressure?

Cougar232 · Jan 4, 2006

I did not perform a leak down test. Will a catch can vent better than hooking it back up the the intake. How bad are my numbers in the cylinders. Just seems strange that the old valve cover with a massive hole leaked less than a nice new tight one? Any other mods to improve pcv setup or increase cylinder to ring tightness through crankcase evacuation?

Cougar232 · Jan 4, 2006

Also I have a high idle around 2500K cold & 2000K warm and Im only getting 10/in.Hg vaccum at idle. When letting off the throttle under load itll spike down to 15in/in.Hg of vaccum. Boost is set at 10psi according to my aftermarket gauge.

Cougar232 · Jan 4, 2006

Ok after lots of searching, I just hooked the valve cover vent to the intake back up. The result was awesome, not a damn leak came out of the cover even under boost and driving, a complete turnaround from last week. I also notice the butterfly in my throttle is not closing all the way when at idle. I also plan on going through all vaccum lines on manifold and replacing them to get some better vaccum at idle. For surging on the highway I believe the BOV is leaking or venting at 3psi part throttle, I plan on replacing those gaskets on the cold side. I stii have oil leaking out by the main front seal I think with the new oil pump and excessive blowby I blew out my new seal I put in? I will wait until better weather to fix that seal since it only leaks a quart a week at most(only a dsm..lol). Any other suggestions now that I am a step forward I appreciate. Thanx.

Cougar232 · Jan 6, 2006

Ok I drove it finally today after weeks of sitting, runs ok but now it is still lekaing some oil out of that weep hole near the timing belt. It must be from the crappy autozone pcv vlave? I order an OEM today and an oil reurn gasket that I never replaced to minimize sum of the leakage down there.

Cougar232 · Jan 12, 2006

Ok how to find an oil leak? I cleaned up the valve cover, and I had the car warm up to normal, then I still noticed no oil leaking on top of the valve cover, I then I had my chick get in and spool up the turbo(A/T powerbrake) and after a few 5-10psi spurts sure as hell the oil creeped out of the BOLT!! closest to the weep hole. So it is definitely not coming out of the weep hole. Bolt was a little loose so I took it out put RTV on it and torqued it back down. I have yet to install my OEM PCV Valve. SO does this still mean I am getting blowby in large amount in the crankcase????

Black Widow · Jan 17, 2006

yai got the same problem, let me know

Cougar232 · Jan 17, 2006

The OEM PCV Valve is worth its weight in Gold. This valve was super tight and I couldnt get any air through it unlike the one from autozone. I also redid those vaccum lines near the coolant hose that helped out 1-2 in./hg of vaccum also. No oil is coming out of the cover now under boost. I do you a wicked leak near the crank pulley and it think its the main seal since it like misting out oil? EVerything is brand new front case and all gaskets and seals. Im thinking of replacing the front main and putting a lil RTV around it to kjeep it happy. ANY CHANCE THAT I BLEW MY NEW MAIN SEAL DUE TO THE WICKED AMOUNT OF BLOWBY AND EXCESSIVE PRESSURE BUILDUP IN THE CRANKCASE< I ALSO DID AT ONE TIME RUN SOME THICKS AS OIL AND HAD HIGH OIL PRESSURE WITH MY NEW PUMP?

New valve cover peep hole leak? Blow-by?

Cougar232

NitrousPete

iowaboostin

oldman

Cougar232

oldman

Cougar232

DSMLIFESTYLE

Tenacious-B

Cougar232

Cougar232

Cougar232

Cougar232

Cougar232

Cougar232

Black Widow

Cougar232

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