Blowing the Dipstick Out and Smoking on DECEL

[tsi1991awd]

OK, my car has been sitting for about the past 4 months while I have been working on it. I replaced the turbo and exhaust manifold, converted to external gate, upgraded injectors and some other stuff that really isn't relevant to this problem.

Today was the first time I got her running and went for a drive. Everything was fine until I got into boost in 3rd gear. She started to smoke some and when I let off, there was a ton of smoke bellowing from the exhaust. It was burning oil.

I thought maybe it was just burning off cleaner I had sprayed before but nope, it still did it...most gears under boost will not smoke except 3rd and I believe 4th. Never really got past 3rd. Decel is when the heavy smoke comes on and when it is at idle, it will go away. When I am driving normal it goes away. After boosting and at decel immediately after, it smokes and smokes and smokes.

The dipstick blew out as well. Spit oil everywhere. BUT the rubber on it is extremely old and it slides in and out with ease, so I crimped the upper portion of the tube just a bit so it wouldn't pop out like that again.

I am sure there is excessive crankcase pressure causing this problem...going to buy a new PCV tomorrow and see if that fixes the problem. Would a bad PCV cause it to smoke like that, or is there a deeper problem? When I parked the car, before working on it, it did not have any smoking issues or dipstick blowing out. I didn't do any type of head work to the car or anything so I don't know....

 

[jay_vi]

drop the exaust and check if there is oil in it you may have a fualty turbo.

 

[tsi1991awd]

I pulled the old PCV valve out (this was a cheap Auto Zone unit) and it still rattled...but the rattling was slow and sounded "muffled". When I shook the OEM unit, it rattled with no problems and sounded normal. So I'm not sure if it was the PCV valve or not that is the problem.

I am letting Seafoam sit in the cylinders tonight and in the morning I will crank the car over and let it all come out and then put it through the brake booster and in the oil and drive the car a bit. I'm not sure at this point....probably the piston rings, and if so

 

[Calan]

I pulled the old PCV valve out (this was a cheap Auto Zone unit) and it still rattled...but the rattling was slow and sounded "muffled".

This is because of the crap that has collected inside, and the Autozone valve probably has a plastic orifice in it as well. Try cleaning it out with some gasoline and then test it again.

When I shook the OEM unit, it rattled with no problems and sounded normal. So I'm not sure if it was the PCV valve or not that is the problem.

Did you put air pressure to the IM side of the valve to see if it leaks? Excessive CC pressure is usually created while under boost, and if the PCV valve is the cause it's because it's not holding boost or is stuck open, allowing boost to enter the CC through it from the IM. If you are running the additional check valve (which I think you said you are), your CC pressure isn't coming from here.

If the PCV valve is clogged and stuck closed, you'll probably get a drop in fuel economy and a rough idle, but in that case it's not the cause of the excessive CC pressure either accept for maybe a very small amount under vacuum conditions. (FWIW, I measured .2 psi max CC pressure that was directly related to bypassing the PCV valve functionality).

**********

So... I'll say it just one more time; just check the damn compression and do a leak-down test already.

Seafoam isn't gonna tell you squat or help with your excessive CC pressure and smoking issues; especially by adding it to the oil. You may get lucky and have something free up in the combustion chamber, but it's not likely since you said the motor was just rebuilt.

BTW - What do you mean by "putting it through brake booster"? Are you talking about using that line to feed Seafoam into the IM with the car running? (I hope that's what you mean). If so, just use a small vac line into the "P" port on the TB...it's much easier to access and deal with while keeping the throttle open, and keeps Seafoam out of the booster's inline check valve.

And stop worrying about it until you have a reason too.

 

[907dsm]

^^ listen to that guy.. he knows what he talking about obivously. good luck man.

 

[tsi1991awd]

This is because of the crap that has collected inside, and the Autozone valve probably has a plastic orifice in it as well. Try cleaning it out with some gasoline and then test it again.



Did you put air pressure to the IM side of the valve to see if it leaks? Excessive CC pressure is usually created while under boost, and if the PCV valve is the cause it's because it's not holding boost or is stuck open, allowing boost to enter the CC through it from the IM. If you are running the additional check valve (which I think you said you are), your CC pressure isn't coming from here.

If the PCV valve is clogged and stuck closed, you'll probably get a drop in fuel economy and a rough idle, but in that case it's not the cause of the excessive CC pressure either accept for maybe a very small amount under vacuum conditions. (FWIW, I measured .2 psi max CC pressure that was directly related to bypassing the PCV valve functionality).

**********

So... I'll say it just one more time; just check the damn compression and do a leak-down test already.

Seafoam isn't gonna tell you squat or help with your excessive CC pressure and smoking issues; especially by adding it to the oil. You may get lucky and have something free up in the combustion chamber, but it's not likely since you said the motor was just rebuilt.

BTW - What do you mean by "putting it through brake booster"? Are you talking about using that line to feed Seafoam into the IM with the car running? (I hope that's what you mean). If so, just use a small vac line into the "P" port on the TB...it's much easier to access and deal with while keeping the throttle open, and keeps Seafoam out of the booster's inline check valve.

And stop worrying about it until you have a reason too.

I did not fiddle around with the old Autozone valve much. I popped the new OEM one in and left it at that. I will try and clean the old one tomorrow to see exactly what is up with it.

Also, I am running a check valve between the IM and PCV valve and yes, it is facing the right direction so it shouldn't be allowing boost into the crankcase. I am going to swap the valve out with another one tomorrow just to see if possibly it is a faulty check valve.

I will do the compression test tomorrow after I try the seafoam crap. I am already having it sit in the cylinders so might as well do that. If it doesnt work then oh well....can't say that I didnt try you know?

Also, I was talking with my wife and the car has actually been sitting for over 6 months...had old black oil in it and the intake manifold and exhaust manifold/turbo were off for a long time and the valve cover was off for a while. Not sure if it sitting like this with old oil caused anything to stick or what?

 

[Calan]

... the car has actually been sitting for over 6 months...had old black oil in it and the intake manifold and exhaust manifold/turbo were off for a long time and the valve cover was off for a while. Not sure if it sitting like this with old oil caused anything to stick or what?

That little piece of information changes things a bit.

You could have corrosion issues in the cylinders and could definitely have some sticky rings. Maybe you'll get lucky with the Seafoam and free it up. It also wouldn't hurt to drain the tank and put some fresh fuel in it.

Post up your compression and leak-down test results. I'm curious to see how it looks now.

 

[tsi1991awd]

Did BLT. Found 2 leaks....but there is air getting into the crankcase. I turn the motor by hand (socket on the crank pulley) and it doesn't go away. It escapes through the breather hose on the side of the valve cover. I disconnected the line to the PCV and that is NOT the problem. There's no air coming from there at all. So with that disconnected, there is still air getting into the crankcase.

So does this scream rings, or could it be the turbo seals? The intake and air filter had a shit ton of oil in it, but I am assuming it was blowing out through the breather hose.

 

[Calan]

Hook your BLT tester up after the turbo (on the UICP or TB) and test it again. If you still have leakage from the breather even with the motor a bit past TDC, it's starting to look like rings. A leak-down test is your best bet to be sure though.

 

[jwahl16]

You might as well check shaft play on the turbo as well. I know you said you replaced it but was the "new" turbo used or rebuilt? When my turbo blew there was a lot of oil in the intake and ic piping. I don't know much about engine internals so listen to what everyone else has been saying about checking the rings.

Good Luck!

 

[tsi1991awd]

Hook your BLT tester up after the turbo (on the UICP or TB) and test it again. If you still have leakage from the breather even with the motor a bit past TDC, it's starting to look like rings. A leak-down test is your best bet to be sure though.

Ran the car down the road and back, pulled the plugs immediately after shutting the car off and proceeded to do the test. I had to let it crank 8-9 times before the needle stopped moving and here are the results:

Cylinder 1 - 155
Cylinder 2 - 155
Cylinder 3 - 153
Cylinder 4 - 160

After doing the compression test, I disconnected the valve cover breather tube from the intake (I have a Dejon intake with welded nipple) so the valve cover was VTA. I ran the car WITHOUT the intake on. I noticed a tiny bit of smoke through boost but no smoke whatsoever on decel.

After driving it for a few minutes, there was no smoke under boost and no smoke on decel. Sooooo I'm not sure if the seafoam ended up freeing up a sticking ring or what the deal is...compression is good and now there's no smoke.

Any clues as to what happened?

 

[iminadaze]

Those pesky squirrels like to leave nutshells in the engine bays of cars, not saying that this happened to you, but next time you leave parts off your car for an extended period of time make sure you seal any openings. Even small critters can cause big problems

 

[ryan90tsiawd]

I had this problem before, and it turned out to be a faulty PCV valve on the valve cover. It was allowing boost to get in past the check valve into my crankcase

 

[tsi1991awd]

Where'd you go, Calan
I posted my compression results.