We bought our Aveo diesel in March 2012. Error code 89 has been a part of our lives ever since, mostly during the winter. Last Friday, after having been to the dealer almost a month, we got the car back with a new engine, and today error code 89 popped right back upOur dealer is clueless. Are you sure about the software update? The car is even worse now, no pull and uses too much diesel. We are so tired of this.