Last year, while often showing lightning speed, Swiss-born Grosjean became known as F1's 'first lap nutcase', following a series of incidents that culminated in the first race ban issued by the FIA for many years.
Lotus, however, gave the 26-year-old another chance, but so far in 2013 - whilst keeping out of trouble - Frenchman Grosjean has been struggling for pace.
At the same time, in the sister E21, Kimi Raikkonen is already a 2013 winner and a mere 3 points from leading the drivers' championship.
Grosjean has been bemoaning a mystery cause of his woes beneath the skin of his black and red racer, in China dropping from sixth on the grid to just ninth at the flag.
"What is the problem?" he is quoted by France's RMC Sport. "My driving style? The tyres?
"I do a lap, the car works, I do another, it does not. We need to understand the reason for this inconsistency," added Grosjean.
Boss Boullier, however, is confident Grosjean and his engineers will find a solution soon.
"He didn't manage to perfect his car with the tyres and so he's had a little more trouble (in China)," he said.
"But it is nothing dramatic; everything will go back to normal.
"He just needs to get it working perfectly with his team and his engineer, without losing too much time," added Boullier.
"He will get there, there's no problem."