I have a C5 with an LS3 in it. When I installed the engine I put on the correct Crank reluctor wheel but I am not sure if the motor has the correct cam wheel for the cam sensor - I bought the motor with the front cover already on (it has an aftermarket cam). Since the motor has been in teh car it has been hard to get it to idle. Sometimes it goes from around 950 to 2000 rpm and often tries to stay at 2000 rpm while driving (Like cruise control). I am trying to get a feel for whether or not it has the right cam wheel in it; hope to avoid tearing the whole front of the motor off....

I am gettiing the code P0343.