The Eternal City giants, who lost 2-1 at Sampdoria last weekend, go into Sunday's encounter with Cesena at the Dino Manuzzi stadium in fourth position and eight points behind Milan.
They have collected just one win in their past five games on the road and Ranieri wants an improved display this time.
"We are struggling in front of goal when playing away from home and this is something we have to improve on," said Ranieri, whose side have found the back of the net twice in their last two outings.
"We must continue to work hard and get results in order to get back into the scudetto race.
"I expect an improved performance from my players at Cesena."
Alexander Doni will replace the suspended Julio Sergio in goal for Roma, while defender Philippe Mexes is still sidelined through injury.
Captain Francesco Totti is expected to return to the starting line-up having come on as a late substitute against Samp.
Totti is set to partner Mirko Vucinic in attack with Marco Borriello relegated to the bench.
Cesena held Roma to a goalless draw in their opening match this season and coach Massimo Ficcadenti believes his team can take more points off the Giallorossi.
"Roma are a great team with top players," he said. "We expect a difficult game on Sunday but we are on a positive run and we will be ready to play."
Ficcadenti has reason to be upbeat as his side have not lost in their last three league games.
The promoted outfit held Genoa to a goalless draw last weekend to climb away from the drop zone.
Cesena hold the last position of safety, one point clear of 18th-place Lecce.