Yes the do it's part of the ETCM ( Electronic Transmission Control Module) and it connects to the engine.
It does not have a modulator
A vacuum modulator is used to apply pressure to the throttle valve. The modulator senses the pressure from the manifold and increases when the engine is under a heavier load.
The 1996 Mercury Villager modulator valve can be found on the firewall in the engine compartment. The modulator valve will be on the passenger side of the firewall.
On some of the older vehicles the vacuum modulator controlled the shift points of the transmission by using the vacuum supplied from the engine.
On a Turbo 350 transmission, the vacuum modulator line connects to the intake manifold. This connection allows the modulator to receive manifold vacuum signals, which helps control the transmission's shifting characteristics based on engine load and throttle position. Properly routing this line is essential for optimal transmission performance.
The vacuum modulator on a 300zx should be located on the rear of the engine. It is on the passenger side at the top, close to the firewall.
Typically, you can find the transmission modulator valve near the rear of the transmission. Its function is to control and regulate pressure.
The 1997 Chevrolet blazer modulator valve is located on the firewall in the engine compartment. The valve will be on the passenger side of the firewall.
The 1992 Nissan modulator valve can be found on the firewall in the engine compartment. The valve will be on the drivers side of the firewall.
shift control modulator where is it located 2001 bonneville
The vacuum modulator is on the front of the transmission. The modulator is a round valve and should have a steel line running from the top of the engine(next to the throttle body) down to the valve.