Help!!
 

I have the 2003 Hummer H2. Couple years ago i had a sign reduced engine power. So i went to the local mecanic shop and then fixed throttle body" p2145. And couple month ago i had a same sign reduced engine power. So i went to the local mecanic shop again. And then i fixed pedal position. And finally 3days ago i had same sign.. So i went to dealership. They said battery problem. Then i want to fix it. And In the morning i pick up the car, and when i back to home have a same sign again.... What should i do? I paid alots of money, i'm sick tired.....

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