Transmission will intermittently slip out of gear after coming to a stop

CL1180

MEMBER
2006 CHRYSLER PT CRUISER
2.2L
4 CYL
2WD
AUTOMATIC
70,000 MILES

Hi, the transmission will intermittently slip out of gear after coming to a stop and wont kick back into gear until a high RPM is reached. I have replaced both the speed sensor and input sensor. I also flushed the fluid and replaced the transmission hydraulic solenoid. I'm not sure if its a vacuum problem or there is another issue that could be causing the problem. There's no strange clicking or clanking. No hard shifting and seems to be fine other than the intermittent problem. Does anyone have any insight or suggestions? I'm a intermediate mechanic and can handle most issue on my own. Just can figure this one out. Thank you for any input.

4 Replies

KASEKENNY

MECHANIC
18,907 POSTS

The likely cause of this since you flushed the fluid is the pump is not supplying the proper pressure. This is either due to a failing pump or there is excessive clearance in the unit and that is causing the pressure to drop when the idle is low. Then when you bring the RPMs up the pressure comes up due to the pump spinning faster and it supplies the needed pressure to apply the clutches.

However, the other likely cause is low fluid level so I would suggest starting with that.

See below for the process. Then if you have the ability to check the transmission fluid pressure, let us know what that is when the transmission is hot.

Let us know what questions you have. Thanks

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