I have a 2004 GMC Canyon 3.5 5speed 4x4. thruck has almost 150 thousand miles. I have gotten in the truck twice and the truck wont start. Just clicks. It'll then say reduced power. i put the jump pack on it and it read 12.5 volts. With the pack on it still wont start. After sitting it'll start and runs fine again. The battery is in it is only a year old. The throttle body and mass airflow have been cleaned with in the past 50 thousand. Any ideas?