Im running a gsr nos plate kit and i've went through two bottles only at 75 shot. Now my car burns oil and backfires constantly without using the NOS. Also my idle jumps to 1.5k at times when I am stopped. I Checked my plugs and they were corroded. I changed them and now they corroded again a week later. I know my car is broken but what could it be and what am I looking to spend???