water in exhaust/yellow foam on oil cap
 

The Xs has been sitting for 16 month .3 times a week i start it up , but everytime i start it i notice water coming out of the exhaust.why is there water in there and where is it coming from? Since the Xs been sitting i haven't change the oil even though it very low. I then remove the oil cap and to my surprise i notice yellow foam on it,What in the hell is that? So i started wiping it clean, it wasn't oiley it was more like wet.Could that be from the Xs sitting and moisture build up into the engine? Can anyone help me with this mess. Thanks !

Just a condensation.Water in the exhaust is a common thing in colder weather,haven't you seen a car/truck infront of you taking off and dripping water from the exhaust pipes?
It's so common here in Canada,the pavement is wet for at least 15-20 meters after a traffic light stop line.
Oil filler cap mayonnaise is a common thing for l4 and l6 engines.

The water is a byproduct of the combustion process; normal.
The 'cheese whiz' is an indication of condensation in the engine and crank case, due to no long, hot 'runs'.
Starting it up '3 times a week', or even every day, is not the rec'd method. Either 'store' the car, until next full use,
or start taking it for a real run around Gotham City.

I rec'd a full warm up/hot, and then get/do a good oil change.

Then, skip those starts & idles, or starts and a couple laps around the block, and drive the sumbitch.
GL, mD

See this thread, esp post #9:
http://www.xoutpost.com/bmw-sav-foru...iller-cap.html

Response is most appreciated thanks guys!

those startups are bullshit. Don't do them. If you start go drive it. You are probably making it worse with the little, not fully warmed up starts.

Oh those million mile oil changes are bullshit too. I do mine every 6k miles, and have not seen the cheese at all. My car only warms up fully about two times a week. NYC as well.

Agree with posters above, all that condensation and warming/cooling cycles are brutal on the engine. Don't ever start it unless you are going to drive it long enough to get it good and hot.

Storing a car is harder on it than driving it. Get the oil changed every year. As MD says, do a hot oil change to clean it out.