I posted this in 2nd gen area, but may be technical enough to put here also.

I just replaced the vac lines on my 87 TII & finally removed the vac spiders. The purge control valve is bad. The diaphragm inside under the spring has a hole in it. Now, this looks like it does the same thing a PCV valve would on a piston motor. You have 2 lines run to vac signal & one that connects to the "crankcase". The 2 lines are reference signals, correct & the valve is basically just a check valve that allow the crankcase to vent back into the intake. Am I tracking correctly on this so far? The Mazda part is like $45. A Fram PCV valve is maybe $3 at Wal-Mart. Has anyone replaced the Purge Control Valve with a PCV valve? If so, any idea what the brand/part # was?

 

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