Crankcase Ventilation System Failure (PCV/Flame trap)
All 1993-2000 850, S70, C70 and V70 models (as well as most 2001 2007 S60, S80, V70 and XC 90 models) use a complicated crankcase vent system to prevent the build u of pressure inside the engine. Since the mid 70’s Volvo owners have had problems with this system clogging up with oil deposits. Once the system plugs up, crankcase pressure builds high enough to cause oil to be forced past engine seals resulting in oil leaks around the engine. Another problem with this system is the many small vacuum lines used become brittle and crack, rendering the system inoperable as well as causing idle and drivability issues. Since the lines are buried under the intake manifold, it’s difficult to diagnose. To keep the system operating properly it’s a good idea to visually inspect the lines every other oil change and completely replace all the associated components every 80-100,000 miles. We’ve put together handy kits that make it easy to order the correct parts.