Value with sensor unplugged

[basti]

Hello everyone, I have built a small pressure sensor using an ESP8266 and an ADS1115 (ESPeasy firmware of course).
It works pretty well so far. The only thing that bothers me is that as soon as I unplug it, I still get a pressure value or the ADS outputs a voltage.
I've already tried to eliminate this with a pull-down resistor, but that doesn't work so well (I get a negative pressure reading).
Do you have any idea how I can solve the whole thing in an elegant way, so that I only get "0" as a pressure value or possibly also "unplugged" as a test?

[TD-er]

What is the range of expected values of this sensor?
If it is an analog sensor, adding some pull-up or -down resistor will introduce an error in the reading.
Maybe if using some high resistance value, the error is not an issue.

How is the sensor connected to the ADS and which sensor do you use?

[basti]

What is the range of expected values of this sensor?
If it is an analog sensor, adding some pull-up or -down resistor will introduce an error in the reading.
Maybe if using some high resistance value, the error is not an issue.

How is the sensor connected to the ADS and which sensor do you use?

I am using an analog sensor. It has an output of 0.5 - 4.5 V. The sensor is connected directly to pin A0 of the ADS1115. In "idle" mode, i.e. when the sensor is disconnected, the ADS outputs a voltage of about 1 V. I have already tried using a 10 kOhm resistor, but unfortunately this is not the solution. The pressure value only goes negative as soon as I connect the sensor, but I get back to 0 bar (I set this with the formula). However, I have not yet tested whether there are larger deviations upwards (when I increase the pressure).

Best regards
Basti