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2002 MERCEDES-BENZ SL

3.0L I6RWDAUTOMATICgas
Repairs0Labor593Torque3477Fluid7DTC698Battery1Maintenance0Recalls0
P1661high severityPowertrain

Fuel Injector Voltage Fault Cylinders 1 and 4

on 2002 Mercedes-Benz SL 3.0L I6 · RWD

What this code means

The ECU detected a voltage fault in the fuel injector circuit for Cylinders 1 and 4. These cylinders share a common injector driver circuit, and the fault affects both injectors simultaneously.

Symptoms

  • Check Engine Light
  • Misfires on Cylinders 1 and 4
  • Rough running
  • Loss of power
  • Rich or lean condition

Common causes

  • Faulty injector driver circuit in ECU
  • Wiring short or open in shared circuit
  • Failed fuel injector Cylinder 1 or 4
  • Connector corrosion
  • Power supply issue to injectors

Diagnostic steps

  1. Test injector resistance Cylinders 1 and 4
  2. Check shared circuit wiring
  3. Inspect connectors for corrosion
  4. Test ECU injector driver output
  5. Monitor injector pulse width

Repair notes

Repair wiring in the shared injector circuit or replace the faulty injector.

Other Powertrain codes on this vehicle

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