It is on the low side line as it runs across the firewall under the hood, between the engine and the firewall, generally closer to the passenger side of the vehicle.
NO it can not as there is a check valve located in the filler neck.
You did not say what size engine but in most cases the PCV valve is in the valve cover.
Did this to my 98 Malibu v6, the low pressure valve is on line beside fire wall behind engine, it has blue protective cap on it. high pressure valve you would not use has red cap on it located beside radiator/condenser. You don't say what year your Malibu is so this may not apply to you if your unit uses the R12 refrigerant.
If it has one, it will be located on the fuel rail.
on 2000 3.1 it is on passengers side between engine and firewall,about 1 foot down..
The 2003 Chevrolet Malibu PCM valve can be found on the firewall in the engine compartment. The PCM valve will be on the passenger side of the firewall.
It is just below the lower radiator hose.
A 2000 Chevrolet Lumina has a modulator valve located on the side of the transmission. It is designed to control pressure inside the transmission and adjust shifting.
In the valve cover.
The 1999 Chevy Malibu with the 2.4 engine does not use a PVC valve. Instead the system uses an oil/air separator that can clog up and cause the same symptoms.
It is located in the right valve cover.
The 2002 Chevrolet PCV valve is located on the outside of the air intake housing. The valve will be on the back of the housing.