If there is any residue on the spark plug, it will not produce a sufficient spark for the engine ignition.
You shouldn't have to clean them, and if you go to the trouble of removing them, you should replace them, they are very inexpensive.
No there should not be any oil where you plug your spark plugs into
I would recommend the OEM spark plugs, AC/Delco. Excellent plugs.
spark plugs = the number of cylinders your car has. Tercel should be a 4 cylinder so 4 spark plugs.
Generally, to replace spark plugs on a Subaru vehicle, the spark plug boot should be removed. Then, the old spark plugs should be removed using a socket wrench, and replaced with new ones.
Clean plugs new ones maybe new points
most spark plugs should be checked and gapped annually. if your spark plugs are used up you should replace them
You should replace the spark plugs when your car won't start first time but does eventually.
Depends on the type of spark plugs. Factory plugs around 70 - 100k depending on the condition of the plugs. I would replace the spark plugs out with some AC Delco iridium plugs they will last you 100k+.
The spark plugs are located right under the exhaust manifolds of both sides of the engine. You should just follow the spark plugs wire from the distributer.
The spark plugs on a 1999 Mercury Cougar are located under the cover of the engine. The spark plugs should be changed approximately every 60,000 miles.
It should be at 0.O25 on standard spark plugs and O.O35 on resistor on resistor spark plugs.