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I have a 91 with a 305 TBI. Are there two PCV valves? Or just one? I’m assuming the valve on the driver side valve cover is definitely a PCV valve. I can pull it out and shake it and hear a nice metallic sound. It is connected to the throttlebody at the vacuum line.
But what is on the passenger side valve cover? Is that just a hose that goes to the air cleaner? Or is there a PCV valve in there as well? This one I cannot pull out of the valve cover as easily.
From: Franklin, KY near Beech Bend Raceway, Corvette Plant and Museum.
Car: 1992 Pontiac Firebird
Engine: 5.0L L03 TBI
Transmission: 700R4
Axle/Gears: 2.73
Re: How does the PCV system work?
Passenger side is (CCV) Crank Case Ventilation and driver side is (PCV) Positive Crankcase Ventilation. Vacuum draws in engine blow by through the PCV valve on the passenger side of the engine and clean fresh filtered air is draw in to replace that volume of air drawn out on the rear passenger side of the engine through the CCV tube that leads into the air cleaner housing on the side where it pulls clean fresh air through the little filter assembly inside the air cleaner.
Passenger side is (CCV) Crank Case Ventilation and driver side is (PCV) Positive Crankcase Ventilation. Vacuum draws in engine blow by through the PCV valve on the passenger side of the engine and clean fresh filtered air is draw in to replace that volume of air drawn out on the rear passenger side of the engine through the CCV tube that leads into the air cleaner housing on the side where it pulls clean fresh air through the little filter assembly inside the air cleaner.
There is just one PCV valve.
I think I get it now, does this crappy diagram I made make sense? Is there any type of valve where the CCV hose meets the passage side valve cover?
Flow direction reverses at wide open throttle
Flow is based on pressure difference and Bernoulli's at the intake diameter
You can measure crankcase pressure and set it correctly to OEM wet sump target 0.5" to 1.5"Hg
I made a video of how to diy using the cheapest possible components
Turbo and N/A both breath from the same place (just after air filter tube) in ALL OEM Engines
At cruise flow reverses from WOT and the PCV valve is open
Here is one for N/A engine with numbers so you can see what you are measuring against
