Curious speed behavior
 

Hello
I connected my arduino severino to lcd power, vss and fuel injector, configured mpguino program (vss 2485 for kilometer) but when I test it strange things happens

1. speed and distance occurs only when I;m driving more than 40 km/h
2. Speed is rising ridiculous (last time 400km/h)

Please help me :(

Got a schematic for your car that you can share?

no I do not have it.
For vss signal i connected behind the speed dashboard(and I'm 90% sure that its correct) and for ignition like mpguino FAQ says to ignition ground