Hi guys, new here. I’ve found lots of threads about overheating but I’m wondering if someone’s ran into the same problem as me before. I’ve got a 2003 disco and when I’m at idle or low RPMs I start to overheat, fast, while this is happening my heater cuts out. When my disco is driving on the highway or up a canyon it runs just fine at the correct tempeture with the heater also working. I can be in freezing tempetures though and if I’m just rolling slow I overheat super fast. Anyone have any idea on if this is a particular thing you’ve ran into before? Thanks for help in advance.

 

 

Yeah, sounds low on coolant. The pump does not create enough differential pressure across the heater core at idle to pump through it (could be plugged). After bleeding the system using the bleed screw, let the system cool off then remove the expansion tank cap and rev the engine to 2000 rpm. Level will likely go down as the pump pushes coolant through the heater core

 

Add coolant and BLEED IT ON A HILL.

 

Mine runs hotter in cold weather. Best i can tell the thermostat housing gets cold so the thermostat doesn't open but based on the heat cutting off i agree there might be a bubble. What temp does it get to

 

Found this also
https://landroverforums.com/forum/discovery-ii-18/hotter-temps-colder-weather-54202/

 

Heating up "fast" is likely more related to level or flow but check your fan clutch as well. A rolled up newspaper should not be able to stop the fan at idle when the car is hot. If it does, you need a new fan clutch. Search here for particulars on what to buy.