A multiple championship-winning marque with the now-defunct Techeetah squad, DS switched to the Dragon Penske squad for the beginning of FE's Gen3 era, but has found it hard to replicate the kind of success it enjoyed during the last rules cycle.
In the opening three races across Mexico City and Diriyah, DS Penske could only manage a best finish of seventh, leaving it seventh out of 11 manufacturers in the championship standings heading into this weekend's Hyderabad E-Prix.
Vandoorne admitted that DS Penske has "work to do" to recover from its early season struggles, but couldn't provide a definite timeline as to when the outfit will be able to challenge for podiums and victories again.
Asked how long it will take for DS to return to the front of the grid, Vandoorne told Motorsport.com: "It's hard to judge. It's never easy to make a revolution from one weekend to another but we will take it step by step, but the most important is to take a step forward.
"The first few races have been quite difficult for us. It's mainly that we are lacking a bit of overall performance, especially in qualifying and being out of position [on the grid].
"We've got some work to do. Quite a lot of changes are happening for this weekend, which is a new circuit as well for everyone.
"There is always constant improvement. I think we can do a little bit better with the tyre understanding, optimising the set-up a little bit more, the run plan during the practice sessions and qualifying.
"So [there are] quite a few new bits and we will see the result of it this weekend."
Vandoorne's teammate Jean-Eric Vergne won both his FE titles with Techeetah and moved to Penske as part of DS switching its factory team partner for the Gen3 era of Formula E.
The Frenchman expressed confidence in DS' ability to bounce back after an underwhelming start to the season, citing its previous results as proof that it will be able to return to the front in Formula E.
"We have a very good team of people working together," Vergne told Motorsport.com. "We won many races, many championships together. If one team can come up back to the top, it's this team.
"We are working hard on the sim to improve the car. Let's see this weekend how it goes. We are making steady progress and if we can just do little bit by bit it is going to be good."
