After qualifying 18th for race one aboard the new DS Techeetah E-Tense FE21, introduced for the first double-header after the revised April 5 homologation window, da Costa climbed eight places up to 10th but retired on lap 20 with a puncture.
On Sunday, wet-dry qualifying conditions for the group one shootout meant da Costa qualified down in 15th but he bagged six points for progressing to seventh at the flag.
This was aided by an inside move on Sebastien Buemi while using attack mode before passing the sister Nissan e.dams car of Oliver Rowland over the start line using fanboost.
Da Costa heralded these as “the best overtakes of my life”, telling Motorsport.com: “I have an onboard [camera] so somebody should dig them out.
“Between Saturday and Sunday I did the best overtakes of my life, some of them slightly over the edge. I had so much fun, two races really coming from the back.
“It was a shame with a puncture [but] we managed to capitalise on it and bring some points back home.”
Da Costa reckoned two-time teams’ champion DS Techeetah had already identified several areas to develop the E-Tense FE21 in time for the Valencia double-header across 24-25 April.
He said: “There’s still a few things we could have done better on the background to make my life a little bit easier in the car.
“This is the good thing about this team, everyone is so open minded and so relaxed when it comes to improving.
“We already know four, five, six areas that we know what things to do better next time.
“It’s just one of those weekends where nothing came my way, I really had to scrape hard to get something out of this weekend.”
When da Costa was asked to pick out the main differences between last season’s car, in which he won three races to dominate the title race, and the new E-Tense FE 21, he said: “It’s little quieter actually on the powertrain side.
“There are some improvements in terms of driveability and tools that we have to set-up the car as well regarding the powertrain.
“I am expecting some tracks to help us more than others. For sure, it’s a step forward from last year.
“The good thing is that I know we have a competitive car, it’s a winner. It’s a matter of time until we until we get back up there.”