I think that at idle, an M104 engine may go up over 110 degrees but usually this happens after the engine is well warmed up by highway driving for instance. Prolonged stop and go driving will do this too. In any case the auxilliary fans should kick in and cool it down fast, although it may cycle up to the high temps if the driving conditions persist. This happened to me over the winter in some monstrous holiday traffic jams around NYC - almost 3 hrs of stop and go traffic. It prompted me to install the resistor mod which is discussed at length in some other threads. My car has not seen temps over 100 ever since.
As to the thermostat cover, I would think that torquing it evenly is only due diligence. I haven't found the procedure in the CD to do it yet - if I were to hazard a guess about 15 ft-lbs, others please verify. There is a bleeder port right on top of the housingwith an allen screw.
Head gasket failures - tough call on the long block, new design on replacement gaskets seem to fix it. Wiring harness, definitely because the insulators do degrade faster with higher temps - but this was a materials issue.
1993 300e-2.8 - gone now <sigh>
"Do not adjust your mind, it's reality that's malfunctioning"
Last edited by jsmith; 04-24-2002 at 07:20 AM.