Moisture around oil cap.

[ynot]

This seems to be a common problem on the 2250/2350 running in the north when it gets cold, the last 2 years I've seen multiple posts pop up on Facebook about this problem.

Unfortunately nobody has a definitive solution
aside from the usual suspects bad head gasket or egr cooler.

One theory I read from the car world is the sludge a combination of condensation and unburnt fuel from rich cold temp starting mixtures that doesn't get a change too evaporate. Like a 15min drive just getting the engine warm enough too begin evaporation the water fuel so it rises you shut the engine back off an it cools too the sludge building up over time.


This is just my theory I have no proof but I guess it's possible the isx has the same problem rich starting fuel/air mix + condensation ending up in the oil, it warms up starts too rise up an some heads too the oil fill neck but!! Since the oil fill neck is behind the rad in the direct path of the frigid winter air its cooling an buikding the sludge over time.