Ford Tempo/Topaz 1984-1994 Repair Guide

PCV Valve


See Figures 1 and 2

Most models do not use a PCV (positive crankcase ventilation) valve. Instead, an internal baffle and an orifice control the flow of crankcase gases. But there are some later model 2.3L engines that have a PCV valve incorporated into the emission system. (See Section 4 for more details on emission controls).

The PCV valve is located on top of the valve cover or on the intake manifold. Its primary function is to purge harmful vapors from the crankcase, via a system of vacuum and fresh air drawn through the crankcase. Proper operation of the PCV valve depends on a sealed engine.

Signals of a malfunctioning PCV system include rough idling, oil present in the air cleaner, oil leaks or excessive oil sludging.

A simple way to check the PCV valve is to remove it from its rubber grommet, and shake it. If it rattles, it is functioning. If not, replace it. In any event, the PCV valve should be replaced even 30 months or 30,000 miles. When checking a PCV valve, it is also a good idea to inspect the hose attached to it as well as the grommet. If there are any cracks in the hose, replace it as well.


  1. Remove the valve, with the hose still attached from the rubber grommet using a rocking both and forth motion
  3. Loosen or remove the hose clamp securing the PCV valve to the hose. Use a twisting motion to remove the valve from the hose. Inspect the the hose and grommet, and replace if needed.
  5. Coat both ends of the PCV valve with oil, install the new valve into the hose, sliding the clamp into position, and finally install the valve into the rubber grommet.
  7. Start the car and check for any air leaks.

Click image to see an enlarged view

Fig. Fig. 1: Remove valve with a back and forth motion

Click image to see an enlarged view

Fig. Fig. 2: Remove any breather hosing attached to the PCV valve