I just changed out the thermostat in a 03 Grand Prix 3100. When I put it back together it was chugging and dying. I took apart the intake and throttle body and cleaned the crap out of it. The car no longer dies but it revs randomly and the RPMs will stick at a certain point like 3k or 4k and jump around. The car does this when sensor number 4 from the picture is unplugged (i'm assuming its the throttle position sensor) and also when number 3 is unplugged (i'm assuming its the mass airflow sensor). Anyone know what the problem could be. Also if you could explain the numbered sensors in the picture it would help.