Based on the description and the dealers findings, your, new to you, Cruze had its oil overfilled at least once.I just took delivery of my 2014 Cruze Diesel today, and was digging through the service records he provided me. During the test drive, he mentioned something about a problem with the turbo that was dealt with under warranty, and I found this entry (I'm guessing he just got the terminology confused... didn't seem too keen on the technical aspects of his Cruze- the dealership had him going at $85 every 3 months for an oil change!):
Customer states that vehicle made loud rattle noise on startup at idle, seemed to try to accelerate... could not get vehicle to turn off.
Found excessive oil in charge air cooler causing engine over rev condition. Glow plugs high resistance.
So they replaced 2 glow plugs at 18,xxx miles, and cleaned out the CAC and radiator, and that seemed to fix the issue. Any thoughts on this incident? I don't expect to see any further issues regarding this matter, but being brand new to this motor, I wanted to get your opinion(s).
The overfill caused the excessive oil to get 'wipped up' and blown into the crankcase vent, forcing raw oil into the intake charge and depositing it into the intercooler (CAC).
The oil that was accumulated in the CAC was drawn into the throttle.
Since a diesel burns oil, the engine could (and did) run on the oil coming through the intake......this is called a 'runaway'
In this situation, there is no throttle control and the engine runs without the fuel injectors providing any fuel.
The two glow plugs may have shown high resistance because they were oil coated.....they likely would have cleaned up on their own but the dealer chose to exchange them in the interests of avoiding a return of the car with a second problem.
Odds are favorable, no harm done.
To you and all diesel owners: this engine oil spec. is 4.75 Qts. with a filter exchange.......I don't think I can stress enough the need to check the oil level IMMEDIATLY after the car has had a oil change service......there have been far to many owners that had the engine inadvertently overfilled.
Congrats on the 'new to you' car.