I was told it could be a vacuum leak

JAMESTPOWELL87

MEMBER
2012 MITSUBISHI GALANT
2.4L
4 CYL
2WD
AUTOMATIC
137,099 MILES

Transmission won't go into gear put it I n reverse it does nothing even if I rev it no movement in neutral it it don't move but if I rev in neutral It feels like it wants to roll forward an inch or two when I throw it in drive it doesn't move but if I rev it high it will move forward very slowly I replaced whole valve body and solinoids attached to valve body 5 total and replaced a neutral safety switch

1 Reply

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

This sounds like either you have low fluid level or you have an internal failure such as clutches or seals.

https://www.2carpros.com/articles/automatic-transmission-problems

You would need to do pressure testing to verify the front pump is supplying correct pressure for the transmission to work.

I attached the pressure testing procedures and charts for correct pressure.

From your description, it sounds like you need a replacement transmission.

Roy

CAUTION:
The transmission fluid temperature should be between 70 - 80°C (158 - 176°F) during the test.

Check the transmission fluid level and temperature. Check engine coolant temperature.

Transmission fluid level: "HOT" mark on the dipstick
Transmission fluid temperature: 70 - 80°C (158 - 176°F)
Engine coolant temperature: 80 - 100°C (176 - 212°F)

2. Raise the vehicle so that the wheels are free to turn.

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3. Connect the special tools (3.0 MPa (427 psi) oil pressure gauge [MD998330] and adapters [MD998332, MD998900, MB992018 [5A/T]]) to each pressure discharge port.
NOTE:

2ND: Second brake pressure port
UD: Underdrive clutch pressure port
LR: Low-reverse brake pressure port
DR: Torque converter release pressure port
DA: Torque converter apply pressure port
RV: Reverse clutch pressure port
OD: Overdrive clutch pressure port
DIR: Direct clutch pressure port[ 5A/T]
RED: Reduction brake pressure port[ 5A/T]

4. Restart the engine.
5. Check that there are no leaks around the special tool port adapters.
6. Measure the hydraulic pressure at each port under the conditions given in the standard hydraulic pressure table, and check that the measured values are within the standard value ranges.
7. If the pressure is not within the standard value, stop the engine and refer to the hydraulic pressure test diagnosis table.
8. Remove the O-ring from the port plug and replace it.
9. Remove the special tool, and install the plugs to the hydraulic pressure ports.
10. Start the engine and check that there are no leaks around the plugs.

STANDARD HYDRAULIC PRESSURE TABLE

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