My 2010 buick lacrosse wont start.

Hello, A concern where the engine will crank but not start indicates a problem with one or more of a few areas. First, you could have a fuel delivery problem. You could have a lack of ignition spark. Engine timing could be disrupted. Engine compression could be compromised. Proper air intake to the engine could be interrupted or too plentiful. Testing hands on is required to find out what is happening. Replacement of the transmission and the various things done during that repair could have stimulated a problem. Did the engine start ever after this work? Also, the crankshaft position sensor likely was not failed or has any bearing on the no start issue. A trouble code indicating loss of sensor signal almost never means that the sensor has failed. Good luck. www.repairpal.com/repair-shops