Having problems with your GMC Cars & Trucks ?
2005 gmc envoy runing rough po302 i replace plugs and "2 coil now po300 runs rough
Have you replaced the fuel filter. also check the battery new cars use a lot of power and that could cause a random misfire code. if those are all good then check for a vacumm leak. you can do that with carb cleaner by running the vehicle and spraying around the intake manifold or vacumm lines and listen for a change in the motor
Repair Help & Product Troubleshooting for GMC Cars & Trucks
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