The engine U1073 Code explains about the car engine problem and by the proper verification of the car engine, it is possible to know the right meaning of the code. The engine U1073 OBD 2 code on cars with electronically controlled automatic transmissions, the 3-4 shift solenoid is responsible for actuating the hydraulic circuits to activate clutches or bands that modification gears secret the automatic transmission. Do not follow any wrong meaning for solving the car engine problem. You should keep getting appropriate information for solving the car engine problem. However, a test drive is recommended after solving the car engine problem.