Dear aleekat,

Hope you're well. 940s with Rex/Regina engine/ignition management have a coolant temperature sensor mounted in the radiator's passenger-side plastic side-tank. Cars with Bosch engine/ignition management do not have this sensor.

Radiator makers should supply a plug (#1274052, $3, at a US-based Volvo dealer) and grommet (#1378869, $6) for cars that do not have an in-radiator temperature sensor.

Lubricate the plug with dishwashing liquid. I use a large water-pump pliers gently to press-in the plug. I use a loop of brass wire - over a radiator fin and the top transmission coolant pipe - to secure the plug.

I do this to prevent another plug "blow-out", which - happily - did not result in any overheating, thanks to: (a) a cold engine on a chilly day, (b) a very short journey, and (c) a retro-fitted low coolant indicator light.

Hope this helps.

Yours faithfully,

Spook