excessive crankcase pressure

[srteater]

This is my first post so bare with me. I have a 97 gst and the other day I had the dipstick blow out of the tube. I called Extreme motor sports and they told me this is a common problem and that sometimes it is just the orings on the dipstick tube and other times it means that the rings are going bad. It just happend for the first time about 2 weeks ago and now it does it every time that i hit full boost. Could it be because the drop in temp that it has got this bad this fast. Also i am wondering if this is because i have bad ring would it be okay to rig the dipstick in the tube till i can afford to do the bottom end or will this just cause more problems. also if i lower my boost over the winter will this help with crankcase pressure.
Thanks SRTEATER

 

[gurmanator]

check the p.c.v. valve....I would just replace it.

 

[T is for TURBO]

check the p.c.v. valve....I would just replace it.

agreed

 

[drivemusicnow]

agreed

I would also replace the O-ring on the dipstick. Sometimes these get bad in cold weather and a fresh one will help it stay in place. If this doesn't work, then you do have too much crankcase pressure, and you don't want to "rig" the dipstick to stay put.

At that point I'd replace the PCV valve, if you're still having problems, I'd try the crank case vents from Dejontool, or a fixture that will allow you to run a line from your valve cover to your exhaust with a venturi fitting. this will actually "pull" the air out of the crankcase, causing a vacuum.

 

[srteater]

i have a new pcv valve and i had to replace the the dipstick about 2 months ago i had a blown manifold gasket and when i took the manifold of i broke the top of the dipstick it was still useable but i just got a new one from mits. I have the crankcase vent running threw a oil catch can right now. If i run the vent threw the exhaust isnt the going to pull oil thew the exhaust and make the car smoke like crazy

 

[srteater]

If i was to reroute my catch can to the intake instad of just having a crankcase filter on the on side would this help pull out excess pressure

 

[srteater]

when you say before the turbo do you mean if i put it back in the stock location in the intake pipe

 

[oldman]

1. Compression test, both dry and wet. This will tell you the conditions of the piston oil rings.

2. Boost leak test, this will tell you if you're leaking boost through either the pcv valve or valve seals.

3. Did you replace the pcv with an OEM unit? Most aftermarket ones as well as some OEM's are know to leak right out of the box, did you test for leaks before you intall it? Is the pcv routed back to the intake manifold? How is the breather valve routed?

4. Any smoke out of the tailpipe?

 

[srteater]

the pcv valve was replaced by a oem unit and is routed the same way it comes from the factory the crankcase is routed threw a catch can and the back in the intake in the stock location. I do a boost leak test like every week because i allways blow throtle bodie gaskets. I had a compresion test done by extrememotorsports about a month ago when they were trying to diagnose another problem. it checked out fine but that was before this problem started.

 

[oldman]

Give us specific numbers, "checks out" doesn't cut it when you're troubleshooting. What were the compression numbers? Dry and wet? How much pressure was the intake holding (on your boost gauge, not the air compressor) during your weekly leak test? Did you open the oil cap and listen for leaks into the crankcase?

 

[srteater]

i dont know what the numbers were on the compression test i was not there when they did it and they didn't give me any #s they just told me the did a compression test and that was not the problem so i just went along with it. On boost leak test I generaly run it at 20lbs though I only run between 18-19 lbs on the street. I have listened inside the oil cap in the past but not recently

 

[oldman]

i dont know what the numbers were on the compression test i was not there when they did it and they didn't give me any #s they just told me the did a compression test and that was not the problem so i just went along with it. On boost leak test I generaly run it at 20lbs though I only run between 18-19 lbs on the street. I have listened inside the oil cap in the past but not recently

In that case, now that you're experiencing dipstick popping out, I would repeat both compression and leak test yourself, pay special attention to crankcase leaks. Also make sure that the 20psi is what is shown on the boost gauge, not how much you're pumping in from the air compressor gauge.

 

[srteater]

Well i will give it a try and i will post my results

 

[srteater]

I rerouted the catch can back into the factory location in the intake pipe and have no problems the day after i did it I was out on a local road where people go to race and I ran a honda I put the car under full boost threw 3rd gear and it never came out then on my way home i raged on it the whole way and it has not come out since so I otherwords I belive that this fixed my problem.
Thank you for all off your help

 

[oldman]

I rerouted the catch can back into the factory location in the intake pipe and have no problems the day after i did it I was out on a local road where people go to race and I ran a honda I put the car under full boost threw 3rd gear and it never came out then on my way home i raged on it the whole way and it has not come out since so I otherwords I belive that this fixed my problem.
Thank you for all off your help

It's good that you got it solved but it's just a bandage, the question of what is causing the extra pressure still remains. I would still follow through with them tests when you get a chance just to be safe.

 

[oldman]

Oldman; are you referring to a crankcase leakdown test? Just want to clarify.

Compression and boost leak tests.