I suspect the fuel level was a coincidence. However, the idea that it happened when the power steering pump was under a load, I have a feeling it is related to the idle air control valve (IAC). I'm not sure where you are located, but in the US, the i20 isn't available. As a result, I have no technical info on it.
What I would suggest is to try a few simple things such as cleaning the throttle body and IAC system. Here are two links that explain how to do both. First, I would start by cleaning the throttle body. If that doesn't take care of it, then move to the IAC.
https://www.2carpros.com/articles/throttle-actuator-service
https://www.2carpros.com/articles/idle-air-control-valve-service
I'm here if you need anything, so let me know. Also, if you have other questions, feel free to ask.
If you have the chance, let me know if this helps.
Take care,
Joe
Sunday, June 14th, 2020 AT 4:38 PM