PCV (short for Positive Crankcase Ventilation) is a system that helps a small amount of fuel and oil blown by piston rings return to the air intake. It’s quite common for it to deteriorate over time, leading to all kinds of problems. Failed seals can cause oil to escape, the idle to be unstable, oily smell in the cabin or even higher fuel consumption (due to engine vacuum leakage). Replacing this seal is a good starting point when pinpointing similar problems.
1x PCV grommet
Fits Mazda MX-5 from 1989 – 2005.