87 260E Auto 180.000 Miles. Idle hunts up and down from about 900-1100 in N and 450-750 in drive. had no choice but to adj the linkage so it could be driven, trying to adjust the fuel mixture has no affect. All new Tune up parts and filters. No vac. leaks. Car starts great Hot or Cold, does seem to have higher than normal Fast Idle, 1400 N but no idle hunt till warm, the warmer it gets the worse the Idle drift.

Have also cleaned ICV, no change.

What do I check next