fuel shut off confusing my scan gauge

[talldudenumber5]

i have a 1996 nissan maxima. my scan gauge thinks that there is a fuel cut off (i.e. 9999mpg) when i let off the gas and am coasting but it also does it if am idle at a stop light. i just realized it could not be right since the were still exhast fumes coming ou the other day when it finally got really cold. i am not sure if i need to adjust something or if that would just screw the whole thing up.

just wondering if anybody else had this issue or if i should just turn the fuel cut off thing off

[Weather Spotter]

You need to adjust the throttle plate closed value. default is like 22 take it down to ~ 18 and see if it helps. the value is telling the SG that when the throttle is at XX value it is fully closed. I think my car is at 17 or so.

Your car may not cut off fuel when coating in gear, if so just put the value to 0.