Where is the transmission modulator valve?
intake manifold
The modulator valve is attached to the intake manifold with a vacuum line. It senses intake manifold vacuum and shifts the transmission accordingly: When you press down on the gas pedal, the throttle plate opens and the vacuum is reduced.
What is a modulator valve?
A modulating valve is an automated control valve that can be fully open or fully closed, not just on/off. A modulating valve is a combination of a modulating actuator and a valve. Common valve types are: globe valve, disc valve, and quarter-turn valves (butterfly valve or ball valve).
What is the purpose of a vacuum modulator?
Vacuum Modulator is an engine load sensing device that converts engine vacuum into a transmission valve body input.
What happens when the modulator valve in a car ruptures?
When the diaphragm inside the modulator valve ruptures, transmission fluid is drawn up to the engine like liquid through a straw via the steel vacuum tubing. When burned in the engine, this transmission fluid produces blue smoke from the tailpipe.
How can you tell when your modulator valve is bad?
Check the exhaust of the car for blue-colored smoke. When the diaphragm inside the modulator valve ruptures, transmission fluid is drawn up to the engine like liquid through a straw via the steel vacuum tubing.
How is the modulator connected to the engine?
The modulator is connected to the engine through a combination of steel tubing and rubber hoses. When higher amounts of engine vacuum act on the modulator, the transmission begins to shift earlier and softer. As engine loads increase, vacuum diminishes, causing the transmission to shift later…
How does a vacuum operated modulator valve work?
Vacuum-operated modulator valves are installed in automobile automatic transmissions for the purpose of controlling shift patterns. The modulator is connected to the engine through a combination of steel tubing and rubber hoses.