The Finn had a troubled final day of testing at Barcelona after having also been hit by problems earlier in the winter.
Raikkonen insisted the issues were now resolved.
"We had some problems in testing but we still completed quite a few laps. Of course, you always want more laps, but it is what it is," said Raikkonen.
"We're all going racing and then we'll really see where we're at. I'm not really concerned about reliability or anything like that as it was the same problem which caused us the biggest problems in testing and we're on top of that now.
"You can never be 100 per cent certain of course, but if you look at last season we had problems before the start of the year then we were pretty good when we got to the races."
Team boss Eric Boullier was also positive despite the loss of running.
"We can take quite a bit of confidence following pre-season testing," he said.
""We didn't complete as many laps as we wanted and we did experience a few glitches both technical and physical, but despite this we were able to work through most of the items in our itinerary.
"We are confident that we have made a step forward compared to last year."
Raikkonen, who finished in third place in last year's championship, agreed that this year's E21 should be stronger.
"I think you always want more, but this car is a pretty good starting point and we'll see; hopefully we're fast enough.
"I don't think there's any area where it feels worse than last year's car; so far everything is better. We had good speed last year, but not enough to win the championship.
"That means we need more speed this year. If we can get just a little more from the car and keep our consistency, with some better results at the beginning of the year, then we should have a much better chance."