Note: Mitsubishi recommends replacing spark plugs with platinum or iridium electrodes every 90,000 km of vehicle mileage, and regular spark plugs every 45,000 km. However, given the quality of gasoline in the CIS countries, it is recommended to replace spark plugs when they actually fail.
1. Removing the spark plugs.
a) (GDI engines) Remove the engine cover.
b) Disconnect the wiring connectors from the ignition coils.
c) (MPI engines) Disconnect the high tension wires from the spark plugs and remove the spark plug guide tubes with the ignition coils as an assembly.
Caution: When removing and installing high-voltage wires, be sure to hold only the rubber tip of the wire, not the wire itself. Improper handling of high-voltage wires may cause internal breaks in the wires.
Note: Before removing the wires, mark their relative positions to avoid confusion during installation.
d) (GDI engines) Remove the spark plug guide tubes with the ignition coils as an assembly.
d) Use a clean cloth to remove any dirt from around the spark plugs that may get into the spark plug mounting holes.
e) Using a spark plug remover, remove the spark plugs from the cylinder head.
2. Check for burnout of the electrodes or damage to the insulator of the spark plugs. Also check for significant carbon deposits on the central electrode, damage or cracks in the sealing washer, and the condition of the enamel of the insulator at the end of the spark plug. Replace the spark plugs if necessary.
3. (Spark plugs for MP1 engines) If there is carbon deposits (electrodes are black), remove them using a wire brush or a spark plug cleaner (sandblasting). Use compressed air to clean sand from the threaded part of the spark plug.
4. (Spark plugs for GDI engines) The electrodes of spark plugs used in GDI engines darken even when the ignition system is working properly. However, this is not a sign of malfunction, since the soot covering the electrodes burns off faster when this type of spark plug is in operation compared to conventional spark plugs. To check whether the spark plug is working properly, measure the resistance of the spark plug insulator. If the measured value is less than the maximum permissible value, replace the spark plug.
The maximum permissible value is 1 MOhm
5. Using a spark plug feeler gauge, check that the spark plug gap is within the nominal range.
Nominal value:
- MPI Engine 1.0 - 1.1 mm
- GDI Engine 0.5 - 0.7 mm
Recommended spark plugs:
Engine 4G15-GDI:
- NGK (type 1) — BKR5EKUC
- NGK (type 2) — IZFR5B
Engine 4G93-GDI:
- NGK (Type 1) — BKR6EKUC
- NGK (type 2) — IZFR6B
MPI engines:
- NGK BKR5E — 11
- NIPPON DENSO — K16PR-U11
- CHAMPION — RC10YC4
Note:
- NGK (or Nippon Denso) spark plug marking: the first character "I" or "S" means a spark plug with iridium electrodes; the second symbol "Z" in the NGK spark plug marking indicates a spark plug with a protruding spark gap.
- The symbols "EKUC" in the NGK spark plug markings indicate a special two-electrode spark plug for GDI engines.
- Mitsubishi recommends installing Type 1 spark plugs in GDI engines. Type 2 spark plugs are an alternative.
Spark plugs for MPI engines.
GDI Engine Spark Plugs, Type 1 (two-electrode).
Spark plugs for GDI engines, type 2 (single electrode).
Caution: For spark plugs with platinum or iridium electrodes:
- Replace the spark plug if the gap limit is exceeded.
- Do not attempt to adjust the gap on these spark plugs.
- Cleaning these spark plugs may damage the electrode coating. Therefore, use a spark plug cleaner to remove carbon deposits and clean the spark plug completely for no more than 20 seconds to avoid damaging the electrode coating. Do not use a wire brush.
[The article was obtained from this portal: MitsubishiMan.ru]
8. (Spark plugs for MPI engines) If the gap does not match the nominal value, adjust it by bending the side electrode.
9. Installing spark plugs.
a) Clean the spark plug mounting holes.
Caution: Be careful not to allow foreign particles to enter the engine cylinder through the spark plug hole.
b) Install and tighten the spark plugs to the specified torque.
Tightening torque - 25 ±5 N·m
c) If necessary, apply silicone grease to the spark plug insulators.
d) Install the spark plug guide tubes together with the ignition coils and tighten their mounting bolts to the specified tightening torque.
Tightening torque - 10+2 Nm
d) (MPI engine) Securely connect the spark plug wires to the spark plugs.
e) Connect the wiring connectors to the ignition coils.
g) (GDI engines) Install the engine cover and pre-tighten the engine cover mounting bolts in the order shown in the figure so that the cover can be moved by hand. Tighten the mounting bolts to the specified torque in the order shown in the figure.
Tightening torque - 3 Nm
Engine 4G15-GDI
Engine 4G93-GDI.