GM bought back my 2013 Cruze with Coolant loss and odor problems after many recalls, repairs and attempts to fix it. I traded for a 2015 Cruze and they said problem was fixed. Well we had coolant loss and odor shortly after getting the new car. I had researched problem and found ECU program is not standard or like other GM cars. The ECU lets the engine get hot in some cases and the gauge does not go up.

There is a 221 deg mode and in some torque conditions it allows the engine to get over 240 deg. In turn the coolant boils and escapes through the tank vent. If this vented coolant gas gets pulled into the car you have the odor. Over time this loss of steam equals about 4 to 8 oz loss in 7500 miles. This repetitive overheat puts stress on the system and seals. I can cause leaks at the coolant pump, tank or heater core.

GM issued many recalls and bulletins but did not remedy the root cause of the problem -The improper ECU program.

I spent over 24 months talking to GM, the factory and the dealership to get them listen. Finally a GM service rep e-mailed the Dealership and said I could change the Engine control program. I bought a HP Tuner interface and credits and modified the program so the 221 deg mode keeps it in that range. Since the change my temperature runs around 221 deg in that mode and has not gone over 228 deg.

Previously I routinely saw the temperature go over 240 deg for short periods. Since I have made the change I have put over 25,000 miles on the Cruze with no coolant loss or coolant odor. -Root Cause and Problem fixed! I tried to feedback this problem and the fix, the dealer thinks it is great but GM will still not listen.

I am sorry for all the Cruze owners with this problem when there is a simple fix for it that I have fed back to GM many times.