My 85 380SE (198k) idles at about 700 in P but drops to just above 500 in D. It idles smooth in both, has normal power, etc. Any idea what to look at? The only reason I care is that the temp goes up at a stop after freeway driving unless I put it in P while I'm stopped esp with ac on. TIA, Jim

__________________
85 300 SD ~ 115K
82 500 SEC Euro ??K
78 450SL 164K