The OEM sparkplugs are the Denso twin-ground electrode variant. They are designed to last up to 60,000 miles before needing replacement. Depending on driving conditions and maintenance history - plug life can vary considerably, most see changes anywhere from 30,000 to 60,000 miles.
Take it to a Toyota dealership
How do I change spark plugs in 2009 Toyota Corolla? whaT TOOLS I NEED
If you do not have any problems with plugs, change them when you replace the timing belt (do not forget to replace the spark plug wires too).
position of spark plugs on 2003 Toyota coralla
6000 miles
How do you replace the spark plugs on a Peugeot 307?
Every year, or as an when the service requires
Corollas has a four cylinder engine, it means it has 4 spark plugs.
Replace them every 100,000 miles.
How to replace spark plugs in a 1989 jeep cherokee?
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+.
Every 60,000 miles.