Car knocks while in park and as I am driving?

2015 GMC TERRAIN
166,000 MILES
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JC1997
  • MEMBER
  • 1 POST
When I start my car, it knocks while in park and as I’m driving. When I go up hills I have to really push on the gas. I’m thinking the compressor is messing with something else in the vehicle.
Apr 20, 2025 at 10:42 AM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
That is easy enough to find out what the problem is, please turn off the HVAC system and take it for a drive to see if the problem goes away. Can you please shoot a quick video with your phone so I can hear the noise? That way I can tell for sure what's going on. You can upload it here with your response.
Apr 21, 2025 at 11:07 AM
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