Transmission-Related Issues:
* Low or Incorrect Fluid Level: Check the transmission fluid level and make sure it's within the proper range. Low fluid can cause slipping and gear issues.
* Transmission Control Module (TCM) Problems: The TCM controls the transmission's operation. A faulty TCM can prevent gear selection or cause the transmission to operate incorrectly.
* Internal Transmission Problems: The rebuild may have missed something, or a new issue could have developed. Problems with the valve body, clutches, or other internal components can cause gear selection problems.
* Damaged Torque Converter: The torque converter connects the engine to the transmission. If it's damaged, it can prevent the transmission from engaging.
* Stuck or Damaged Shift Solenoids: These control the flow of transmission fluid to the clutches. If they are stuck or damaged, they can prevent the transmission from shifting correctly.
Other Possible Causes:
* Engine Problems: If the engine isn't running properly, the transmission won't receive the power it needs to shift.
* Electrical Issues: A faulty wiring harness or electrical connector can disrupt the communication between the TCM and the transmission.
* Safety Switch Problems: The safety switch in the transmission prevents the car from moving when it's in "Park" or "Neutral." A faulty switch can prevent the transmission from engaging.
* Shift Cable Issues: The shift cable connects the gear selector in the car to the transmission. If it's damaged or out of adjustment, it can prevent the transmission from shifting into the desired gear.
Important Note:
* Get Professional Help: A proper diagnosis requires a mechanic to inspect the vehicle.
* Safety First: If your car won't go into gear, it's unsafe to drive. Contact a qualified mechanic for assistance.
It's important to have a mechanic inspect your car to pinpoint the exact cause of the problem. They can then provide a proper repair solution.
