high false value

Hi.. My arduino is attach with gsm shield,icomat 1.1, but when I am receiving sms my analog input give me a high false value? My board is powered by 9v 3a DC adapter..? Can I fix it?

What is a high false value? It it a high value that is not correct or is it a logic one when the condition you are looking for is not true!

The sensor give me a high value which is not correct.. because It doesn't detect that kind of value, For example the potentiometer give me a high value when I am not doing anything about it, the other one is the piezo element, it detects knock when I am not knocking or doing anything.. Sorry for my bad English.

Sketch & schematic?

Sounds like floating connections.

My piezo element is connected with the resistor 1000 K ohms and 5 % tolerance..

Don't ignore that I only having this high value of sequence knock when I'm receiving sms..

See Reply #3.