Pressure coming from valve cover breather during idle?

4g63tcrazy · 10-02-2010

My colt started smoking recently. It progressively got worse and worse til I did a 1st-3rd gear pull today and started smoking constantly (blue smoke-oil). I pulled the intake off and there was a bunch of oil in the intake. I guess not much more then normal since I'm not running a catch can. Shaft play on the turbo is somewhat minimal, but if I put pressure up or down while turning the compressor wheel, it will rub the housing a little.

Another thing to mention is I had the oil changed at my work and had someone else fill it and they over-filled the car by a quart. So I figured that's where all this puffing out blue smoke came from because it just started happening after the oil change.

Today I drained some oil down to the full mark and took it for another test drive. I drove the car for awhile to clear out any oil. It was still puffing smoke, not as much as before but it still did. Then I pulled off the hose from the breather on the valve cover and it was shooting out smoke. Shouldn't it be under vacuum at idle? What would cause it to be under pressure? I would think if it was the pvc valve it would blow air out of there only under boost. Also after a couple pulls I could see where oil was blowing out of my oil cap and spraying. That makes me think it's the pvc but why would I have constant pressure blowing out of the breather?

**Goat Blower** · 10-02-2010

You're probably thinking of the intake manifold which is at 18-19 in/Hg, although there is a minute amount of vacuum in the oil system at idle as well, but a lot less.

If you've got a lot of positive pressure in your crankcase, you're getting a leak from one of the combustion chambers. Sounds like a bad ring in one of the cylinders, might want to do a compression test to be sure.

4g63tcrazy · 10-03-2010

I'll do a compression test tomorrow. The car isn't down on power though or acting funny at all. It runs perfect, but I guess only the test will tell..

CarPsyco84 · 10-03-2010

you have the stock pcv valve? is it working? cause if it used to work and is now plugged it might cause a little bit of smoke out the valve cover, but it shouldn't be that much...

4g63tcrazy · 10-03-2010

I just did a cold compression test. 135-135-125-75

About a month ago cold compression was 185 accross the board. I guess the n/t 4g61 didn't like boost..

**Goat Blower** · 10-03-2010

Yep, the rings in the NT's aren't meant for boost. You can do it on the cheap though and bottle hone the cylinders(if they're not scored), throw some new rings on a good 1G piston/rod set with new bearings of course, and let 'er buck.

4g63tcrazy · 10-04-2010

Yea but I figured the engine would last a little longer on a stock dsm setup at only 10psi. I couldn't slap any 1g pistons in there cause it's the 1.6L 4g61. I have my eye on a turbo 4g61 complete engine right now so we'll see how that turns out.

Alpha D · 10-04-2010

Quote:

Originally Posted by Goat Blower

Yep, the rings in the NT's aren't meant for boost. You can do it on the cheap though and bottle hone the cylinders(if they're not scored), throw some new rings on a good 1G piston/rod set with new bearings of course, and let 'er buck.

I like that idea so much i might try it on mine.