Hi, I have a 2004 GTI VR6 and I haven't driven the car for about a year now. I recently have been trying to diagnose the car and the last time I drove it before it broke down there was a severe coolant leak; however, I couldn't see it because my hood latch was broken. The cause of the leak ended up being my thermostat housing which was not only cracked but had a large hole about 1 inch long and .5 inch wide. I scanned the car with an odb2 scanner and the only engine code that it is throwing is a p2177 which is a system too lean code. I'm wondering if a crack in the thermostat housing (It was severe) could cause a vacuum leak in the system to cause the p2177 code. Before the car officially broke down some symptoms were lack of acceleration, fluctuating engine temps, rough idle (car would want to die and sometimes not start at all), and backfiring every time I shifted through gears. I checked for vacuum leaks and had no luck finding any, and an O2 sensor had been replaced a year prior to when it broke down. Any help would be appreciated thanks.