Hi. For the past 6 weeks the steering has intermittently been suddenly heavy while driving. After Green flag, independent garage and Local Renault garage saying there is no fault, I've finally got the local Renault dealer to experience the problem. However no one seems to know what's causing it and have been advised they are "punting" on it being the computer in the steering column. Hence recommended changing this at a cost of £1650 with no promise of fixing problem. Help what do I do? Car is a 59 plate.