What are the Torque specs for spark plugs on a 2003 Toyota Echo?

Answer 1

15 ft/lb

Remove the plastic cover on top of the engine. (4 bolts) You will see 4 modules connected to electric wires on top of the engine. Those are the ignition coils. They are bolted to the valve cover with a single bolt. Remove that bolt and unplug the connector (I did one at a time) to easily remove the module from the plug. You will see the plug down the hole. Use a 5/8 Inch spark plug socket and remove carefully, engine being cold. Aluminum heads have fragile plug threads. Replace with new plug which should normally be pregapped at .043 in (for Bosch Platinum plugs the gap is .032). Tighten snugly but don't use too much force. (torque wrench at 15 ft/lb) Replace coil module and reconnect wire and you are done. Don't forget engine cover.

Note: The 2000 model echo came with special iridium spark plugs that do not have to be changed for at least 100,000 miles (I changed mine at 120,000).

Most Echo owners consider the Denso (Part #SK16R11) or NGK (Part #IFR5T11) Iridium plugs to be a good replacement for this vehicle and they can both last for 100,000+ miles.