Such signs as a crunching sound that appears when the wheel is turned during acceleration, as well as the vibration and jerking during acceleration indicate a malfunction of the CV joints. In this case, the outer CV joint produces a crunching sound at a sharp start or when turning with the wheels turned out. In the event of a malfunction of the internal CV joint, a crunching sound is accompanied with vibration, even if you drive on a flat road. Diagnostics of CV joints consists in checking the integrity of the dust seals and the presence of traces of grease from under them on the surfaces, as well as in determining the gaps. If traces of grease are visible on the parts, then the CV joint is disassembled and the possibility of repairing or replacing the CV joint is evaluated.