Long story here. 2010 625i overheated after idling for about 15 minutes. Coolant overflowed. Took in for service and tech said "loose hose to radiator - tightened". No more leaks, but still overheated next time it was used. Took to a different dealer. They replaced thermostat & water pump and said wire to engine sensor was frayed & repaired (mice damage?). Next use engine overheat light on dash came on & fan came on. Radiator cap and radiator were slightly warm to the touch. Took it back to dealer they replaced engine sensor. Got it back today and after using for 20 minutes, some in low gear, engine automatically throttled down. Radiator was cool. Could not climb slight incline. Let it sit with engine on & it would then run OK for a little while then throttle down again.
​What else can be wrong? Appreciate any help.