ISUZU Amigo/Pick-ups/Rodeo/Trooper 1981-1996

Distributor Cap and Rotor



Remove the distributor cap and inspect the inside for flash over, cracking of the carbon button, lack of spring tension on the carbon button, cracking of the cap, and burned, worn terminals. Also check for broken distributer cap towers. If any of these conditions are present, the distributor cap and/or cables should be replaced.

When replacing the distributor cap, transfer cables from the original cap to the new cap one at a time. Ensure each cable is installed into the corresponding tower of the new cap. Fully seat the wires into the towers. If necessary, refer to the appropriate engine firing order diagram.

Light scaling of the terminals can be cleaned with a sharp knife. If the terminals are heavily scaled, replace the distributor cap.

A cap that is greasy, dirty or has a powder-like substance on the inside should be cleaned with a solution of warm water and mild detergent. Scrub the cap with a soft brush. Thoroughly rinse the cap and dry it with a clean, soft cloth.

Replace the rotor with a new one if it is cracked, the tip is excessively burned or heavily scaled. If the spring terminal does not have adequate tension, replace the rotor with a new one.


See Figure 1

  1. Disconnect the negative battery cable.
  3. If necessary for additional clearance, remove the air cleaner assembly.
  5. Unplug the engine wiring harness connector from the distributor, or from the distributor wiring connector.
  7. Loosen the distributor cap retaining screws or release the distributor hold-down spring clamps, depending on the specific engine being serviced.
  9. Label and disconnect the spark plug cables from the distributor cap.
  11. Lift the cap off of the distributor.
  13. Note in which direction the rotor head is pointing.
  15. Depending on the particular engine, it may be necessary to remove a rotor retaining setscrew, then pull the rotor off of the distributor shaft.
  17. Remove and discard the distributor cap-to-distributor body gasket or O-ring.

Click image to see an enlarged view

Fig. Fig. 1: Exploded view of a common distributor (some models do not use a setscrew to secure the rotor in place)-1990 Trooper II with 2.6L and 2.8L engines shown, others similar

To install:
  1. Push the new rotor onto the distributor shaft. Make certain it is pointing in the same direction. If applicable, install the rotor retaining setscrew until snug.
  3. Install a new gasket or O-ring onto the distributor housing, making sure that it is seated correctly.
  5. Set the distributor cap back onto the distributor.
  7. Tighten the distributor cap retaining screws until they are snug, or engage the distributor cap hold-down spring clamps.
  9. Connect the spark plug cables back onto the distributor cap. Make sure that they are fully seated on the distributor towers.
  11. Attach the engine harness wiring to the distributor, then connect the negative battery cable.
  13. Install the air cleaner, if applicable.