Help With Scangauge II

On the screen where it lets you monitor what you desire, I have selected the following:

1) AVG
2) MPG
3) TFC
4) Gallons used

Whenever I'm driving on city streets, the MPG option always cycles numbers like it's possessed. I can't ever get a steady read. Sometimes it'll even read 9999MPG.

Is this normal or am is there something wrong?? What would you recommend I do?

Thanks & Happy Holidays.

 

No worries.It's normal.

 

Normal. It gives you a reading on your MPG at that instant. Its also about 2-3 seconds slow so it can seem random. When it reads 9999 it just means that your getting over 100MPG at that moment. Like if your going 70 down a long hill it will just start at 30PMG and increase all the way up to about 80 ish then read 9999. Once your press the gas it will return to 15MPG ish.