I have purchased a used 560 SEL with 127,000 miles on it. All the major service has been done including timing chain, new injectors, spark plugs (bosch copper). I have also set the mixture to read a 50% duty cycle.
The problem is that the engine has a miss to it which comes and goes. At times, the miss will become quite evident as though a cylinder or two are not firing.
I am worried that perhaps a valve is burnt, but do not understand why this 'miss' would then be only intermittent. I have checked almost everything including swapping the Overvoltage Protection Relay with no results.
Also the cruise control only works on occassion, and the clock and oil gauge do not seem to function.
Any advice would be greatly appreciated. Thanks!