Fox Body Oil Separator Install

Follow along as Landan walks you through the step-by-step process of installing an oil separator on your 1986-1993 Fox Body Mustang. During the venting process, large amounts of oil in the form of vapors can coat the intake manifold, which dilutes your air-fuel ratio, lowering its octane level. Thanks to the multi-stage filter system, an oil separator is designed to counteract the oil vapors. The multi-stage traps within a catch can consist of a fine mesh stainless steel screen to prevent fine oil vapors from passing through an aluminum honeycomb filter where the oil is drained into the base of the catch can tank. Drain the tank every oil change, and you will never come close to filling it. Enhance the engine performance in your 1986-1993 Fox Body Mustang and eliminate harmful oil vapors from your intake manifold!

This install will take roughly 30 minutes to an hour to complete.

Tools Needed

• 10mm socket and wrench
• Hose cutter (or a blade of some sort)
• Assortment of rags



Additonal Parts Needed

• PCV Kit With Screen
• PCV Valve Hose

1. Open the hood and locate the PCV valve in the lower intake manifold. Located at the rear of the lower intake and in the center.


2. Remove the valve and grommet by pulling up on the hose.


3. Follow the hose with your hand and remove the hose from the vacuum fitting in the upper intake manifold. Use a pick and a magnet to fish out the metal filter screen.


4. Install a new filter screen in the correct orientation.


5. Feed it into place with the magnet and then fully seat it with a long flathead screwdriver.


6. Take this time to clean and inspect the factory vacuum hose. The hose on this car was very hard and it had developed a few cracks. You can replace it with the correct hose from our site.


7. If you're using the factory style hose, cut it just before the short 90-degree bend to create a straight section.


8. Lightly lubricate the inside and outside of the new grommet with some silicone grease and install the new PCV valve into the grommet.


9. Lightly lubricate the plastic fitting on the oil separator assembly and the PCV valve. Install the long hose on the oil separator onto the PCV valve and then connect the shorter hose with the plastic fitting on the oil separator with the short section of the vacuum hose.


10. When installing the bracket, carefully dislodge the harness clip from the firewall and position the harness out of the way. Pass the bolt through the bracket and then feed the bolt through the opening just above the AC accumulator. Install the washer and hold it in place while you thread on the nut.


11. Verify that the bracket is straight and then use a 10mm socket on the bolt head and a 10mm box end wrench on the nut to tighten the hardware. Reinstall the harness clip.


12. Feed the two hoses behind the intake manifold. Align the PCV grommet and firmly push it down to fully seat it within the lower intake. Route the other hose towards the open fitting in the upper intake manifold and reinstall it.


13. Align the screw holes in the top of the oil separator with the bracket and loosely install one of the Phillips head screws. You'll be able to align the second hole with the bracket and install the last screw. Go ahead and tighten both of these down. Reposition anything that you had to work around and give everything a final once over. After that, you're good to go.

All right, everybody, we hope that this article has helped you better understand how to install a new oil separator on your 1986-1993 Fox Body Mustang. You can pick up one of these Fox Body oil separators below!