Like all other car engine code, this engine P1709 Code is also important thing. You should not ignore the engine code. The car engine code is found for the test of the car engine by the car code reader and check the car engine manually what will be done by an automobile engineer. Manual check of the car engine helps to identify the real problem of the car engine what was not found before. The car engine code explains about the problem by the meaning. It may not accurate relate with your car engine problem. So, you should not fully trust on machine check.