Where is the modulator valve on a Turbo 400?

Where is the modulator valve on a Turbo 400?

Locate the vacuum modulator on the passenger side rear of the transmission. Look at the hose leading to it from the engine and examine it for cracks that could cause a leak. Shut off the engine and replace the hose if any problems are found.

How do you remove a modulator valve?

Steps to Take

1. Lift your Highlander.
2. Remove the vacuum hose, which runs between the intake manifold and the transmission modulator valve.
3. Unfasten the bolts holding the modulator valve onto the transmission.
4. Remove the modulator valve by twisting it counterclockwise.

What does the vacuum modulator do on a Turbo 400?

It is equipped with a vacuum modulator that senses change in the engine’s vacuum due to throttle position and load changes. As these changes occur, the modulator adjusts the shift timing of the transmission according to the demand of the engine.

How do I know if my vacuum modulator is bad?

When you have a bad modulator valve, some or all of the following symptoms will begin to manifest themselves:

1. A whistling sound (from a leaking diaphragm)
2. White smoke coming out of the exhaust (from a leaking diaphragm)
3. Early or late shifting.
4. Hard shifts (usually causing the car to jerk)
5. A rough idle.

What does the modulator valve on a transmission do?

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. The modulator valve will cause the transmission to downshift.

How do you know if your transmission valve is bad?

Symptoms of a Failing Valve Body

1. Delayed Garage Shifts. One of the most common symptoms of a failing transmission valve body is a delay in shifting or harsh shifting.
2. Incorrect Shifting. When driving, you could notice the transmission shifting into higher or lower gears at the wrong time.
3. Shift Flares.
4. Gear Slippage.

How many gears does a 350 Turbo transmission have?

three

Is a TH400 better than a TH350?

The TH350 uses a mechanical kick down switch, whereas the TH400 uses an electric one. A lot of people claim that he TH350 has less drivetrain loss than the TH400, which means that all things being equal, the TH350 is going to get more power to the rear wheels from an engine with equal power.

How much power can a Turbo 350 handle?

The Stage 1 TH350 is rated up to 450 hp.

How much does it cost to rebuild a Turbo 350 transmission?

A good TH350 is going to cost more than $200. I spend more than $200 on parts to rebuild one (stock) and I get good pricing on the parts since I’m a transmission shop. This doesn’t upgrades, labor, shop overhead, etc. The days of having an automatic transmission rebuilt properly for $200-400 are done.

Are all Turbo 350 transmissions the same?

Externally, all the TH350 transmissions look the same; however, internally there are some differences. Depending on the engine size of the car the transmission was removed from, it can have anywhere from 10 to 18 friction discs and 10 to 18 steel clutch plates inside.