Car accelerates up to 20 mph and wont reverse. codes P1078 P1084
 

Im having trouble with my 2003 Infiniti g35. I have an automatic transmission. It won't reverse, it accelerates at only about 15-20mph, it barely touches 2000 rpm. Two codes are showing up P1078 P1084 and also, I'm using nissan computer module. Is it really the cam sensor needing to be replaced? Please help