My car starts fine but then will idle at 500. I step on the brake and change it into gear (reverse or drive) and it stalls with a little shaking. I had replaced the Idle Air Control valve about a year and half ago and just took it off to clean it to see if that was the issue. This did not fix it. My brother hooked his OBD tester to it and it gave him the code P0320. With that information he put on a new crankshaft position sensor and I believe a position speed sensor. My car worked fine for 5 days and now the problem is back. Stalls everytime I change gears.