sd_dracula

Just did a 10km/30 min run through light traffic and during this time the engine temp never went above 77c.
Is that too low for an 05 520d? 4c outside temp
Apparently should be high 80s/low 90s?
Main thermostat can be acting up? No warnings though.

Anzafin

I agree, the right temps should be around 90°C in that outside temperature.

- Antti -

Mobmatrix

Way to low. Start by checking the EGR thermostat, i guess both the egr and the water thermostat are totalt open.
Good luck

sd_dracula

I also need to go on a proper motorway drive to check, not just traffic.
But I have noticed a slightly higher mpg so it indicates towards the stats.

530dE60

Very common but extremely under reported thermostat (often both egr and main) problem with a few recent threads over on bmwland.co.uk and bmw5.co.uk A lot more diesel owners there !

sd_dracula

Did a longer drive today and it even got to 97c while stationary, in traffic for a few seconds.
Once moving it stays between 80-90c.