Fuel and air

P0201 — Cylinder 1 Fuel Injector Circuit Malfunction

Severity: medium Drive with care, to a shop

What P0201 means

The engine control unit monitors the electrical circuit that drives the cylinder 1 fuel injector. It pulses the injector to spray fuel and checks the circuit for a normal response. P0201 sets when it sees an open, short or other out-of-range condition. The cause may be the injector, its wiring or connector, or, rarely, the driver inside the control unit.

Symptoms

  • Check Engine light on
  • Cylinder 1 misfire, often with P0301
  • Rough idle
  • Reduced power and sluggish acceleration
  • Poor fuel economy
  • Hard starting
  • Fuel smell

Possible causes

  1. Failed cylinder 1 fuel injector (open or shorted coil)
  2. Open or short in the injector wiring
  3. Corroded or loose injector connector
  4. Damaged harness (chafing, heat damage, rodent damage)
  5. Faulty injector driver in the PCM (uncommon)

How to diagnose

  1. Scan all codes and freeze frame data, and look for P0301 or other injector codes
  2. Inspect the cylinder 1 injector connector and harness for corrosion, damage and a secure fit
  3. Measure injector coil resistance and compare it with the manufacturer spec
  4. Check for supply voltage and a control pulse using a noid light or scope
  5. Test the wires from the injector connector to the PCM for opens and shorts to ground or power
  6. Swap the injector with another cylinder and see if the fault follows it
  7. Check fuel pressure and fuel trims
  8. If the wiring and injector test good, check PCM power, grounds and the driver

Common fixes

  • Replace the cylinder 1 fuel injector
  • Repair the wiring or replace the damaged connector
  • Clean the terminals and restore a secure connection
  • Repair or replace the PCM if its driver has failed

P0201 on different brands

Ford · manuals
On 2024-2025 Ford gasoline engines, P0201:0A may appear and indicates an open or short condition; it describes the detected monitor condition, not a confirmed failed part.

Questions and answers

Can I drive with a P0201 code?

You can drive briefly, but the engine will likely misfire, lose power and use more fuel. A leaking or stuck injector can also harm the catalytic converter, so fix it soon.

What most often causes P0201?

Most often it's the cylinder 1 injector itself or a problem with its connector or wiring. A bad PCM is much less common, so start with inspection and electrical tests.

Why does P0301 show up along with P0201?

If the injector isn't opening correctly, cylinder 1 doesn't get the right amount of fuel and misfires. The PCM logs that as a separate P0301 code.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.