The car goes into failsafe mode after aprroximately 20 miles of driving. turn off for 5 mins and the fault goes away. after diagnostics its showing code 4f85, ratio monitoring clutch e

SOURCE: I recently brought a BMW Z3, it has a auto

Mine has just done the same is in for diagnostic will let you know the outcome

SOURCE: engine cut out doing 70+ on motorway.

Not importantly if they had it might feel jumbling on the road .. this could be the problem to tyr of the car if they do not have equal amount of air them the car loses balance..

SOURCE: BMW (e39 1999) eml and asc lights and in limp mode

Check the ABS brake sensors in your wheels, if they are not functioning properly. It will trigger the computer to engage the ASC auto stability control light as the asc uses the brakes to assist in control. I will also engage the EML engine management light to slow the rev point to limp mode

SOURCE: I have a BMW 2004

I'am not sure but sounds like an automatic choke problem

SOURCE: need to know what "trans failsafe mode" message

Trans failsafe is "Limp" mode, it means a sensor has triggered due to a fault in OBC. You need to bring it to BMW or a competent shop to have a fault scan done to identify the actual cause. Limp mode allows you to drive short distance (so you're not stranded roadside)