One problem related to starter solenoid has been reported for the 2005 Chevrolet HHR. The most recently reported issues are listed below.
Parked 2005 chevy Hhr and key would not disengage from ignition. This is permanent until an new shift assembly is installed as the solenoid holding the key is locked. This happened in the parking lot at the local community college. Having the key locked in the ignition makes the vehicle theft prone. This malfunction is not a driving hazard but creates a theft hazard if it happens where the vehicle cannot be secured, like my home garage.