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Engine smokes only when going uphill

1995 Subaru Legacy wagon.

If I drive up a steep hill for 5-10 minutes, the engine will smoke copiously.

It’s fine when I drive 200 miles over lightly rolling terrain.

The temperature gauge doesn’t get above medium.

It’s been doing this for at least two years (since I bought it from a friend).

What’s the story?

Smoke From Under The Hood Or Underneath The Vehicle Or Smoke Definitely Out The Tailpipe At The Rear ?

From under the hood. The engine.

Make sure the PCV valve, the hose to it and the vacuum port are clear.

How much oil does this vehicle consume?

It seems to consume a normal amount of oil. I checked it 2-3 months after a change, and it was at normal levels. I change the oil every 3000 miles, and the mechanic has never said anything.

How can I find out what the PCV valve, hose and vacuum port are? Is there a picture on the Web somewhere? Should I have a mechanic do it?

It seems so strange that it only happens going uphill, and not while driving 200 miles on a highway. And no change to the temperature gauge.

It sounds like the sump might not be pulling any oil from the pan because of the angle of the car.

I wonder if your engine has an oil leak onto the exhaust manifold when the car is at an angle such as going up a hill. You might raise the front of the car with a floor jack with the engine idling. If it starts smoking, you may find where the oil is leaking.
Also, check the transmission fluid. Maybe you are leaking transmission fluid onto the exhaust system when the car is on an incline.

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Personally, I think that Triedag’s suggested scenario is the only possibility that makes sense.
The problem could well prove to be of another origin, but for the time being, I would suggest that you follow through on his suggestion.

I agree, that is why I asked about consumption. I would look at the transmission, I had one do this. It leaked from the selector shaft seal, but only when the car was at a certain angle. It was hard to find.

I Agree. That Is Why In The First Response, I Asked For Clarification In Regard To Where The Smoke Is Seen.

Ordinarily when " . . . the engine will smoke copiously. " . . . It’s out the tailpipe.
However when it does it only " If I drive up a steep hill for 5-10 minutes . . . " then it’s possibly something spilling onto a hot engine component and smoke comes out the top or bottom of the engine bay.

I Don’t Know Subarus From Spaghetti Sauce. Does This Car Have An “H” Engine Configuration (Horizontially Opposed) ? Any Part Of The Exhaust System Beneath The Valve Covers ?

Could it be a VC gasket that leaks or drips accumulated drops when it tips a little ?


Yes, the engine is an H-configuration, and yes, the valve covers are located above the exhaust manifolds.

same car same problem, ever get it figured out?

Why is it so hard to see the dates on these old inactive threads where the OP has been gone for so long?

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Old thread but new poster so I have an idea . My son has a Subaru & it collects oil in the spark plug wells . These spark plug wells are part of the valve covers & have an O ring type seal that goes bad & allows oil into the wells & the oil lays in there . I can see that if enough oil accumulated in there that it could run out when the car is at an angle . A new set of valve cover gaskets solves the problem of oil leaking into the wells .

I had a valve cover leak once that only leaked when under heavy load- like climbing a mountain would do.

It’s a good place to start looking.