Took it into the shop for oil consumption testing only to be told that their warranty would not cover it and it needs a new engine. Had to do this two times with oil on plugs took it in and they never look at the spark plugs #3 car burning excessive amount of oil anywhere from 1 quart a week to 3 1/2 quarts after driving 600 miles. Have do documents to back that up #2 engine light coming on, diagnostic testing indicated spark plugs need to be replaced. Bulbs can’t be replaced anymore due to wiring burnt ( 1 headlight ) took it in and they didn’t even look at it. #1headlights & break lights going out often. There was/ are other symptoms prior to the failure 1st appeared 11/01/21 O2 sensor, 11/15/21 catalytic converter, 01/28/21 symptoms wo. Yes there warning lampsthat appeared as the check engine light came on each time the exhaust system was malfunctioning. The vehicle has not been physically inspected by the manufacturer or police but has been insoected by insurance representatives. The problem has been confirmed by rivard Buick GMC. This put the owner and the vehicles occupants at risk which is the greatest threat by far. Another safety risk was when owner of car was falling asleep at wheel of car while driving, not knowing there's a leak. The exhaust leak was big enough to affect the oxygen levels, to spring that code. My safety as well as every occupant that ever traveled in the vehicle thus far, was at risk. The pistons could have melted as well could have caught the car on fire. I need not mention that the extreme or excessive temperatures caused severe discoloration where the three- way catalyst is located. Even in mild cases of exposure to CO can cause headaches, dizziness, nausea and fatigue. Overexposure to this odorless and colorless gas can cause death. A broken exhaust system poses extreme danger because it releases carbon monoxide (CO)- an odorless ,tasteless, highly toxic gas, which can travel in passenger area and cause carbon monoxide poisoning. My safety as well as my children's safety was put at risk because there was and still is (even after repairs made from dealership where car was purchased) an issue with broken exhaust system and leak. 1wk after replacement of O2 sensor installment, check engine light illuminated once again. The catalytic converter failed or malfunctioned, an it is available for inspection upon request. The O2 sensor malfunctioned causing check engine light to come on.