A few weeks ago the belt tensioner unit failed while driving. I had that replaced and after that I noticed some hesitation while driving. On Friday I was on the highway and felt more hesitation and when I stepped on the gas I got three error messages. A message engine inspection required, TPMS inspection required, SCBS inspection required. I went to a garage, they checked the oil and said I was low by a couple quarts. They ran the codes and said that the engine was miss firing on all four cylinders. They topped up the oil and the other fluids and reset the codes and sent me on my way. Couple miles down the road the error messages came up again. The car was hesitating and jerking when I was sitting in the parking lot of the garage. Stepping on the gas the car hesitates, gets to about 40 and the hesitation is worse, very little power going up inclines and if I step on the gas too hard the same warning lights come back. The garage told me I need to drive the car so that something in the engine gets re-lubricated. Something (I forgot what they said) was compressed due to low engine oil and that may be why I am having these issues. I*m also overdue for an oil change by about 5000 miles. Car has 125k miles.