temperature gauge light flashing

[obbig]

fitted a replacement engine in my crew cab, a 1.6 turbo diesel 4 weeks fine, then 3 day`s ago in the mornning red light kept flashing. temp went straight up to high and stayed there for about a mile then came down to normal till to day got a little hot any idea`s be for i take it back cheers bri

[kit]

Air lock, has it done it again?

[lhd]

Check water level or sensor.
Rob.

[obbig]

cheers lads cheecked water it was down a bit sorted bri