Despite the Frenchman enjoying a strong finish to the last year, 2014 has proved difficult for both Grosjean and new teammate Pastor Maldonado, with reliability letting the Enstone-based outfit down on a number of occasions, including a gearbox problem in China last time out.
However, Grosjean is confident that the team is progressing and can finish well in Catalunya.
He told reporters: "The gearbox problem was obviously a big disappointment.
"But the overall picture for the whole weekend was 90% positive. We didn't get a reward at the end, but we know we made a step in the right direction with the car."
Grosjean finished seventh is last year's drivers' championship, registering six podiums during the 2013 season.