The Eagles travel to face rivals Brighton on Wednesday night sitting three points clear of the relegation zone and without so much as a shot on target in their last three defeats.
Better results before the World Cup have kept Palace out of immediate danger and they head to the AMEX Stadium 12th in the table.
While recent results will have dented confidence, Vieira has no such concerns about his squad as they aim to address their slide on the south coast.
“When you do well in your first season, people expect you to keep improving but it is not always the case,” said the Frenchman, who earned plaudits for the style of play he brought to Selhurst Park last season.
“I think it is important to understand where we are, what we want to achieve and the direction where we wanted to go.
“Of course it will take time to be consistent and that is why it is important for us, as a club, to remain calm and keep working, keep believing in the players we have in the building.
“I am convinced with the way we are working, I am convinced about myself as a manager, I am convinced with the players I am working with every day and when you see the attitude and the hard work they showed against (Manchester) City there is no question on that side.
“For me, it is all about improving the squad, trying to find the right combinations to create those chances and to score those goals. We will put our heads down and keep fighting.
“I’m feeling the pressure like the other nine managers in the table. This is part of the game. The table doesn’t lie. We need to win games, play in a better way and score goals. I believe we have the quality to improve our game.”
Vieira was full of praise for Brighton counterpart Roberto De Zerbi, who has impressed since replacing Graham Potter as Seagulls head coach earlier this season.
He did, however, point to an easier transition than he underwent at Palace, where he was tasked with altering the playing style to bring in a more attractive, attacking approach.
“He’s done really well obviously with the way they play but the foundation was there before he arrived,” added Vieira.
“They’re a team who like to have the ball, create overloads in midfield and the way they move is difficult to maintain but we have the quality to cause them problems.
“I think they have a really good squad, good players, they have a clear philosophy about how they want to play the game and the new manager comes in and just has to keep doing what has been done the last couple of years.
“Here at Palace, it has been different, the way we wanted to play has changed and of course we need time, stability to really make it more successful and that is why I am working hard with the players to try and play the way we want to play.”