Step daughter has a 12 plate Meriva MKII with a 1.4 non-turbo petrol engine.This evening she phoned and said that she was on the car park of a local supermarket where she'd been shopping for an hour and when she got back to the car and turned the ignition on the temp gauge went straight into the red zone[before she'd started the engine] I went and had a quick look,no coolant loss to speak of[just a tiny leak from the temperature sender]The sender itself can be rotated in the thermostat housing without any effort at all-surely that's not right is it?-basically you can flick it with your finger tip and it'll move.She's ordered a new sender unit for tomorrow[she's borrowed my V70 to get herself to work and back]are the thermostat housing know to crack around the hole where the sender fits?The sender looks to be held in only by a metal clip.The engine says Ecotec on top and the thermostat bolts to the right hand end of the engine.