over revving

Hi. Last night, I started driving as normal, just got on to motoway and car all of a sudden started over revving. Following that, warning sign came up saying Engine overheated and to pull over/turn engine off. RAC came out, first thought turbo, but had a look at said it didnt look bad. Then did...

Hi all. New issue with my van Vivaro 52 plate 1.9 Glow plugs light on with a light just above. It runs ok but over revving. When I put pedal down light goes out when I release light comes back on. When I change gear it over revs. And light come back on until I accelerate. It drives ok though...