1987 560 SL 75k runs perfectly for about an hour and then 02 sensor light flickers and engine sputters. New: distr cap & rotor, ignition wires (Kingsborne factory spec), coil, fuel pumps, fuel pump relay, fuel filter, all temp related sensors. and crank position sensor. It runs perfectly around town or freeway for about an hour, leading me to believe it's temp related.