02-19-2016, 02:52 PM
SES light popped on - P0128, which is probably the thermostat being stuck open. The car has a "hidden menu" where you can monitor the engine temp and sure enough, it stays around 74 when moving with an 80 degree thermostat.
The kicker? I had just started suspecting the M5 of the same issue - needle stays around the 11:00 position instead of being straight up. I'll take that on a road trip tomorrow and if it also stays low in the hidden menu (so far it seems to be the same), it's double thermostat time.
Now to sort out whether to just do the thermostat, or let while-you're-in-there lead to replacing the whole cooling system on a perfectly running 106k mile car.
The kicker? I had just started suspecting the M5 of the same issue - needle stays around the 11:00 position instead of being straight up. I'll take that on a road trip tomorrow and if it also stays low in the hidden menu (so far it seems to be the same), it's double thermostat time.
Now to sort out whether to just do the thermostat, or let while-you're-in-there lead to replacing the whole cooling system on a perfectly running 106k mile car.
2001 M5
2016 M3
2014 Grand Cherokee
Been had: 1984 318i | 2003 S2000 | 1990 330is | 2005 STi | 2005 M3
2016 M3
2014 Grand Cherokee
Been had: 1984 318i | 2003 S2000 | 1990 330is | 2005 STi | 2005 M3