It’s a problem we’ve heard about, but Super Chevy decided to tackle it head on: why does oil end up in the intake of the 2015 C7 Corvette Stingray?
The short answer? Direct injection.
Now, the more explanatory answer.
According to Super Chevy, the use of direct injection allows for more oil vapors into the PCV (Partial Crankcase Ventilation) system. But, there are a few other culprits that could be causing the problem, too.
The dry-sump tank vent can burp oil and, on the C7 Corvette, it will spill into the intake. The oil also may have been overfilled. The C7 Corvette owner’s manual states the level should read 1/8-inch below the top of the hash marks.
The most technical problem, caused by manufacturer design, is the valve cover area spewing oil into the intake. The PCV and dry-sump reservoir was designed to vent into the air intake area. The problem is, while the bad vapors are routed away, raw oil can spill into the intake.
The solution seems to be the installation of a catch can to stop this from happening, which Super Chevy plans to detail in its next series.