Emission light is on and car is making a loud noise when you push the gas pedal. It also runs rough when pushing the gas pedal. At first it was not noticeable, but now is very loud. The car will only go 40 MPH and barely runs.
This sounds like it could be a serious problem for your car. My first recommendation would be to have this vehicle inspected by a certified mechanic as soon as possible to avoid these symptoms turning into larger problems. The list of reasons is quite long for the symptoms that your car is experiencing, but from my experience it definitely sounds like the engine may have gone into limp mode. Limp mode is a sort of fail safe that allows the vehicle to run enough to get it off the road, allowing you to park it safely in a spot away from traffic and freeways. From the description provided, it seems this is a problem you have had for some time and has eventually gotten worse with time. In my professional experience I highly recommend enlisting a certified mobile mechanic to diagnose why your check engine light (also known as an emission light) is on and help get your engine running in tip top shape again. It is important to not drive your Trailblazer until it’s been properly repaired, so the car does not incur more damage.
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