strange analog input behavior

hi
i modified the "analog read serial" sketch in order to read A0, A1, A2, A3.
on my arduino nano, it looks like there is some kind of link between 2 adjacent inputs, if A0 is reading 1023, A1 is reading 148 and it is the same between A1 and A2 but A1 has no effect on A0.
does anyone know about this?, is my nano out of order?
help me please!

The expected maximum input impedance of the analog inputs is 100K Ohms. If you have inputs of higher impedance the sampling capacitor will not have enough time to reach the input voltage. You can compensate some for that by reading the same input pin twice and using the second result.

What is connected to your inputs?

If an input is disconnected (floating) you can expect fairly random results when you read it.

hi
i found empiricaly the problem and you just explained it!, my pulldown resistor were too big, i lowered the values an everything is ok now
thanks for your answer