Wipers going slowly/stopping?

mostly slow wipers are because the mechanism is stiff rather than the motor. take off a link or two (if it has links ) and see if the actual swivel where the wiper attaches is movable freely. if it is a rack system then it is more difficult. generally if the motor is at fault it will just stop.

You're on the right lines. It's the mechanism. Usually the wiper spindles seize. Common on Golf IV and A3.

You can strip and grease the mechanism, or buy a new one- they're not expensive.

Thanks to both, I've saved the £40 cost of a new motor. For anyone else encountering this problem on a VAG car,here is the fix. Take off wipers, remove bulkhead rubber trim, then remove the plastic trim pieces between screen and bulkhead. These were stiff.It didnt help that I thought they slid backwards, they dont, they lift up. The wiper mechanism is easily accessible then, held by 3 bolts. There are 3 pivot shafts, 1 attached to the motor, 2 at either end of the mechanism.2 of these were nearly seized solid, the other was just a bit tight. the mechanism ones are easily remove with a few knocks once the circlip is off. the one in the motor is under a rivetted cover. The rivets are easily drilled out, then on re-assembly, a few 15mm wood screws were a good fit. It seems they seize as the grease has ran out, or water has got in. Either way, all the shafts need a clean up with a file, then a thorough clean of the bush, then liberally grease both, check they move smoothly, and reassemble. Refit the mechanism, then run the wipers without the blades on. The motor will stop at the correct place, then you can refit the blades.