Oil Level Rises by Itself. WTF?

[msmith65]

My '93 Ex runs great, but lately I've noticed the oil level going up between changes. Smells bad, too.

In the carburetor days, we would look for a stuck float causing gasoline to trickle down into the crankcase.

Anybody dealt with this problem on a fuel-injected engine?

 

[mawrazen]

I had the same problem 94 EB EX.

You have a bad transmission modulator valve.

If sucks ATF into the throttlebody via the vacuum lines. Check your ATF, I bet its low.

The part is about $20. I paid a local shop ($100) to install it for me.

 

[joecrna]

Another possibility is water, ie. head gasket.

 

[CDW6212R]

Yes, what color is the oil?

 

[Tbars4]

...Have you checked your radiator level???

 

[HahnsB2]

I would bet on the tranny moulator valve or fuel pressure regulator.

 

[mechjames]

In order to confirm, the best thing would be to send in an oil analysis, to a lab like http://www.blackstone-labs.com

Its either a water leak (head or intake gasket), bad transmission modulator (atf sucking into engine while motor is running), or a fuel problem (pressure regulator or running too rich (needs a tune up))

 

[bisjoe]

Meanwhile, stop driving it. Transmission fluid is high in detergent and will clean out the engine but over time will cause a lot of wear since it is not a lubricant.
Coolant has water in it and will cause internal rust.

 

[firewolfm]

My '94' X has had the same problem and I just recently discovered the modulator valve is behind a heat shield on the top part of the trans. In order to get at it sensably I would suggest going inside the truck and pull back the carpet over the center hump, that will expose the cover that needs to come off to access the modulator valve. There is one bolt holding a clamp and one vaccuum line that goes up to the vaccuum manifold.
It is best to know which trans. is in your X before purchasing a new valve. There are more that one type valve ,but I would just buy the one that is for "all" applications.

 

[msmith65]

Doesn't a leaky modulator valve put trans fluid into the combustion chambers, creating white smoke?

I'm unclear how it would make its way to the crankcase. Especially without smoking.

 

[msmith65]

I changed the fuel pressure regulator. The vacuum line leading from it was soft, wet, and smelly with gasoline.

The engine seems stronger now, as if there had been a vacuum leak associated with the failed part.

Still wondering about that transmission modulator. I once saw a car whose modulator leaked into the vacuum line, and the trail of white smoke gave it away. I lose a quart of of transmission fluid every few weeks (only while driving; no puddle forms, but there is a trail leading from the front seal), and there's no smoke.

 

[mawrazen]

Is you oil level high? if it is its a bad tranny modulator!

 

[Rick]

I want to know how tranny fluid gets into the crankcase from being pulled into the intake and burned in the combustion chamber

I agree with the tell tale white smoke from a bad modulator. In order for liquid tranny fluid to get into the crankcase you would have to be pulling in so much fluid that it wouldn't all burn during combustion letting liquid find it's way past your rings. For that much liquid to be pulled through, I would think your engine would smoke like a pig and run like one too.

 

[mawrazen]

Possible explanation IMO.

The Vacuum lines are connected to the Throttle body. The throttle body is connected to the PCV valve. The PCV valve is installed on the valve cover. The valve covers are lubricated with engine oil. The ATF drops into the block through the throttle body and PCV valve.

THE ATF is heavier than the air being sucked into the engine and settles by gravity in the lowest part of the TB then into the valve cover via the PCV valve.

If you pull your TB you will find red ATF in it.

song: Theres a leak in the hose in the lines to the TB to the hole in the bottom of the sea! LOL

 

[msmith65]

That's an intriguing analysis, mawrazen. All I can see wrong with it is, the PCV is specifically designed not to let overpressure in the throttle body (e.g., from a backfire) into the crankcase. The normal flow of gases is from crankcase to throttle body. The other way would risk triggering an explosion or fire, if, say, a backfire flame were to ignite gases in the crankcase.

So I can't imagine what could propel a liquid from throttle body to crankcase via the PCV. Unless I also have a faulty PCV, which I think would show up at emissions-testing time, if not sooner through other symptoms.

 

[maxxdout]

I have the same issue, trans, modulator valve. I however, didnt know there was an access panel under the floor! this makes my day instead of fighting to get the cat off.