I recently installed the AEM EMS V2... The first problem I faced is "fuzziness in almost all sensors"

Here's what happened:

I have a Euro version S2000 2004 AP1 F20C2. I tried the AEM and the display was erratic for the coolant temp and TPS.. very fuzzy between 1-4% at idle and the coolant is always fuzzy between 90-93 like crazy... and if you push on throttle the fuzziness increase...
also cranking is bad.. when I try to crank the car it takes like 5 cranks to run..

I have a friend of mine who has a Euro Spec AP1...I tried the AEM on his car.. everything was stable...

So it's my car...first I thought maybe because it's a Euro version ?!? but if sensors are different, there should be an offset in values ..not fuzziness?!!?

I assume it's a grounding issue, maybe the car's earthing is not good enough, though on stock ECU.. the car is running perfect ?!?!?!