Bosch 104-158-02-31 Distributor Ignition Rotor

The Bosch 104-158-02-31 is a replacement distributor ignition rotor (also sold under Bosch part number 1-234-332-427) designed to restore reliable spark distribution in distributor-based ignition systems. The rotor mounts inside the distributor cap and transfers high-voltage current from the ignition coil to each spark plug wire in the correct firing sequence, ensuring efficient combustion and consistent engine performance.

Key Features:

• Directly replaces failed or worn distributor rotors with degraded contacts that prevent proper spark transfer
• Built to meet or exceed OEM specifications for fit, form, and function
• 1 kΩ internal resistor to suppress electromagnetic interference (RFI/EMI)
• Manufactured by Bosch — the world's leading supplier of automotive ignition components
• Not remanufactured — supplied as a new unit
• Recommended as part of a complete ignition service interval alongside the distributor cap, spark plug wires, and spark plugs

Cross-Reference Part Numbers:

• Mercedes-Benz OEM: 104 158 02 31 / A 104 158 02 31 / 1041580231
• Bosch: 1 234 332 427 / 1234332427 / 04297
• Replaces Bosch: 1 234 332 406
• Also cross-references: 028851402972

Bosch distributor caps and rotors are constructed from high-quality materials throughout to ensure long service life and consistent high-voltage performance. Replacing a worn rotor at regular maintenance intervals helps prevent misfires, rough idle, hard starting, and loss of acceleration.