McLaren says is working to rectify the issues it has discovered with the new MP4-28 as it seeks to battle back from a tough start to the 2013 season.
Despite showing an improvement in Malaysia, the Woking-based team has been off the pace in the opening two races of the year and are already 62 points behind Red Bull in the constructors' championship.
Speaking in the latest Vodafone McLaren Mercedes phone-in, managing director Jonathan Neale admitted that the team was taking a series of upgrades to China this weekend to try and alleviate some of the issues faced thus far.
"We managed to improve the car between Australia and Malaysia - we were closer on the pace there - and taking the learning from that weekend we're taking a number of upgrades to China," he said. "Some are just part of our routine upgrade package and some are in response to what we're trying to do at the moment. So I think we've got a lot of work to do on Friday as we learn more about the car and learn what if any of the upgrades that we've taken, works. So it will be a very busy day for Sergio and Jenson.
"I believe that we do know where the problems on the car are, but in order to be absolutely sure about that we need to have run the package that we're going to run in China. So the work on Friday is a very key element to it. As always with cars there is no one thing or no one magic bullet, there are a number of things that will restore the performance of the car. We believe that we've got underlying a very good package, but it's clearly not the performance that we predicted."
Neale added that McLaren has been impressed by newcomer Sergio Perez during his time with the team so far, especially considering the difficulties that there have been with the MP4-28.
"I think he's been really good so far," he said. "He's had a lot to learn in terms of getting used to us as a team, the way that we go about things. Obviously he's with a new team of engineers but he's been a real pleasure to work with and everybody in the team has been impressed not only with his driving skills but just the way that he interacts with us. He's fairly inquisitive and so far he's been very adaptable as well. We haven't given him the easiest first couple of races and we look forward to putting that right so that we can let him do his thing.
“I think at the moment we need to get the car up so that it's capable of winning races and then I think there's a lot of pressure on the drivers at that point. At the moment we haven't done that and the drivers have been fantastic role-models for the team, really pushing very hard out there and I'm delighted with both of them."