Where are the spark plugs located in a 1998 Mercury Grand Marquis?
THE SPARK PLUGS ARE UNDER THE INGNITON COIL PACKS MOUNTED ON THE VALVE COVERS. THERE ARE NUTS THAT SECURE THE COIL PACKS, YOU WILL NEED TO REMOVE THESE COVERS TO EXPOSE THE COILS WITH A SPARK PLUG BOOT MOUNTED ON THE END. WHEN REPLACING PLUGS BE VERY CAREFUL NOT TO DAMAGE THE ELECTRODE BOOT. SOME PARTS STORES CARRY REPLACEMENT BOOTS , SOME REQUIRE THE COMPLETE COIL REPLACEMENT WHICH CAN BE VERY EXPENSIVE.
Does a 1985 mercury grand marquis have an external voltage regulator you just replaced the alternator two weeks ago and now it is only putting out 10.2 volts?
The detection of engine oil on the spark plugs of the 2000 Ford/Mercury Grand Marquis is indicative of a mechanical condition. This is a common symptom of worn valve seals or possibly the guides. This wear may be allowing for excess oil to flow back into the cylinder. This can result in emissions problems and or higher engine oil consumption.