It is below the throttle body, mounted in a rubber bracket. Follow the 3/4 inch hose from the air filter box. it goes to IAC valve.
Broken valve spring
The idle air control valve on a 1990 Ford Escort is located on the intake manifold. An idle air control valves function is to control the amount of air that is allowed to enter the engine so the idle can stabilize.
The "PCV" valve is actually called the "flametrap". Its located on the driver's side just behind the intake assembly. If you go to www.brickboard.com they have a great FAQ just for the 700 series Volvos.
To test the Idle Air Control (IAC) valve on a 1990 Volvo 740, first ensure the engine is off and disconnect the electrical connector from the IAC valve. Use a multimeter to check the resistance across the terminals; it should fall within the manufacturer's specified range. Next, apply 12 volts directly to the valve to see if it moves; it should open and close smoothly without sticking. If the valve does not respond correctly, it may need cleaning or replacement.
check your idle control valve located behind the engine
where is the PVC valve located on a 1990 ford ranger 2.3 L
There is no egr valve on a 1990 Mazda MPV 6 cylinder
It could be the Idle Air Control (Idle speed control) valve. Its located on the left side of your TBI and has an electrical connection.
It is behind the thermostat housing on the nose of the engine block. It is in line from right to left with the oil filler cap. There may be another air valve associated with the steering pump but it is not the "idle" air control valve (IACV).
It should be right on the valve cover somewhere.
The PCV valve is located under the MAP sensor on a 1990 Pontiac Grand Prix. The MAP sensor is in the upper plenum.
The 1990 Plymouth EGR valve is located on the outside of the air cleaner housing. The EGR valve can be found on the back side of the housing.