What causes P300, P301, P303 and P304 after driving several miles? The spark plugs were oily, so I replaced the spark plug tube seals, cleaned the tubes and the plugs, and have not had any oil leak since, but the misfires return every Tuesday. I replaced the plugs, which were barely a year old, the distributor, which leaked oil, and had corroded points, and cleaned the wires, which are also barely a year old, with electrical parts cleaner and Q-tips, and then hot soapy water. I dried everything with my compressor before reinstalling.
You should probably not have cleaned the wires with hot soapy water. I’d say you now need to replace them.
How many miles on the car… 250, 350,000 miles ? You don’t say. You also don’t say which engine is in the car.
If there is oil on the electrode tip, the rings or valve guides are likely worn out and fouling the plugs.
2.3l with 208,000 miles. The tube seals were bad. I have not had oil in the tubes since I replaced the seals.
Oil in the tubes does not put oil on the tips of the plugs.