windscreen wipers intermitant stop

If this is an early '90s E-class (W124 or W210) these cars suffered with dry wiper mechanism, that is the mechanism that is under the cover of the lower part of the wiper arm requires re-lubricating. To do this you will find an allen (female hex) bolt at the base of the wiper arm, un-do and remove wiper arm, next remove plastic cover of the wiper mechanism, this is clipped on and slides over the remains of the wiper arm. Once this is removed you will find the mechanism clean off the old grease, using a good bearing grease or castrol 'LM Grease' lubricate both rods and the gearing and then ensure the wiper arm attachment slides freely up and down. Re-assemble and your wipers should now work.