I am attaching the process from the USA version of the Lancer. They did not offer the Lancer in the USA in this year so we don't have that specific vehicle but the Galant was basically the same vehicle. You are correct that this is removed from under the vehicle.
As for the issue, I am not sure this is a pump issue. If it is running like that with all that blue/white smoke I think you have other issues.
I would start with checking the fuel pressure before you replace the pump.
Once we know what the pressure is we can determine the next steps. However, I would start with checking the compression and going from there.
Let us know and we can go from there. Thanks
Images (Click to enlarge)
Saturday, November 21st, 2020 AT 4:11 PM