560SL rich running after warmup
 

This is a repair report.

Symptoms: Good start and running when cold with a higher than normal idle. After warm, intermittent rough running and near stall from a hot restart. Rich running evidenced by black smoke, odor from cat convertor and spark plug color..

Repair: Replace engine temperature sensor that provides input to fuel injection computer. This sensor is located in intake manifold on left (driver's) side just under front edge of air cleaner. Must remove air cleaner to access. Sensor has a green top and two wires attached.

Source: Logic (heat related running fault) and research location and description on ALLDATA. Recommend ALLDATA to any amatuer wrench.

Result: Normal running and idle under all engine temperature conditions.