Eric,
I had a new head gasket installed and we replaced all hoses while the head was removed. I'm sorry to say I still have limp home about every other day. The temps here are now in the 105-115F range. Doesn't seem to make a difference with my car. Our guess is that it is a relay that does not fully pull in when the car is started. as soon as it cools down, I will get back on it.
Anziani
'93 300CE 200K
'95 E420 122K