ESP8266 not stable

I have had a new sensor kit SDS011/BME280 sensor ID 5423193 for a few weeks

It is very annoying that this system fails regularly, i.e. it is not stable.

However, the WLAN connection remains active.

I have already exchanged the Node MCU ESP8266 and flashed it again, unfortunately without success.

What else can I do to make this system stable?

Just get a better USB 5V powersupply with at least 1.5A.
The symptoms are those a weak PSU.

Thank you for responding,
After connecting to USB 5V 3A power supply the same symptom… still not stable…

Is there the wps Option on the Router ?

Can you send me the serial log ? Plug a usb câble and read the serial with the arduino ide or screen in bash


I just flashed the ESP8266 again and oplaced a node of the mesh wifi system near this.

I will try this first.

Router has a wps button.

This is the device status after flashing.

|Firmware version|NRZ-2020-133
|Free Memory|31632|
|Heap Fragmentation|2 %|
|Last OTA|6 min, 58s|
|NTP Sync|1|
|NTP Info| ( reachable: Yes|
|Time (UTC)|Mon Jun 27 15:23:49 2022|
|Uptime|6 min, 58s|
|Reset Reason|External System|
|only errors|
|OTA Return|200|
|Number of measurements|2|
|Time spent uploading|2301 ms|

This looks normal. Can you get the following logs?

I placed a router mesh node near the ESP8266 and the problem seems to be solved.

The WiFi signal is now 100% and connection seems to be stable now.

Many thanks for your help.

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Now something strange occurs. I can see my sensor on PM sensors - Grafana (

but I can’t login with my IP adres (check IP adres on my router)