The maf reading is a extrapolated calculation based on MAP & RPM . As for why these readings arent working for you I dont know . All these worked on my stage0 & stage2 . No codes are being thrown by your ECU ? Im trying to think what sensors/circuts would cause all these parameters to not work , yet NOT throw a code . I cant think of any . I am assuming your not in limp mode , and you have checked all obd2 plugs & ECU connectors for loose connections . If these dont resolve issue , My next acton would be to try to borrow another SRT4 owners gauge & see if issue is in the car or the gauge .
Good luck finding the problem .
