What does fault code P0202 mean?

The control module has detected a fault in the Cylinder 2 Fuel Injector (P0202). The module sees no circuit at all — broken wire, backed-out pin, or a failed sensor. The fault is isolated to cylinder 2, positioned on the inner block section with asymmetric intake runner pulses. This directly impacts individual cylinder volumetric efficiency, firing synchronization, and dedicated harness branch loading. Measurements: • Cylinder 2 Injector – Coil Resistance (Resistance (Ω)): 11.5 - 15.5 Ω (port) / 0.5 - 3.0 Ω (direct injection) [Condition: Connector disconnected at 20°C (cylinder 2)] • Cylinder 2 Injector – Injection Pulse at 180° crank angle (Signal (ms)): 2.5 - 4.5 ms idle / 1.5 - 20 ms under load [Condition: Engine running] • Cylinder 2 Injector – Supply Voltage (Voltage (V)): 11.8 - 14.4 V (port) / up to 65 - 90 V boost (direct) [Condition: Ignition ON / engine running] Oscilloscope: Scope the control side for Cylinder 2 Injector. The trace must show pull-down to < 0.2 V at open, flat saturation, and an inductive spike (40 - 90 V) phase-offset to 180° crank angle. (Scale: 1 ms/div, 20 V/div)

Standard EOBD

P0202 - Cylinder 2 Fuel Injector

Q: What are the symptoms of fault code P0202?

Circuit open detected; control module enters failsafe default strategy Mid-frequency cabin shudder under part-load cruise (1500–2200 RPM) isolated to cylinder 2. Check Engine Light (MIL) illuminated Possible drivability or power reduction Risk of failing an emissions inspection

Q: What causes fault code P0202?

Most likely: Open circuit, damaged wiring harness, or disconnected plug at Cylinder 2 Fuel Injector Mid-block harness fatigue (cylinder 2): Wiring friction against valve cover bracket and hydraulic standing pressure waves in fuel rail between cylinder 1 and 2. Asymmetric intake tumble: Tumble airflow disruption and localized carbon deposits on intake valves of cylinder 2. Channel A: Verify dedicated wiring pins and signal pair for circuit A against the schematic. Likely: Chafed or pinched wiring harness along the signal path to Cylinder 2 Fuel Injector Possible: Internal mechanical wear or carbon deposits inside Cylinder 2 Fuel Injector Rare: Defective internal output driver or reference circuit in the control module for Cylinder 2 Fuel Injector

Q: How do you fix fault code P0202?

Compare signal voltage and resistance between circuit A and companion circuit B at module connector. Swap component on cylinder 2 over to cylinder 3 and clear DTCs to confirm if fault follows. Smoke test intake manifold runner gasket at cylinder 2 to rule out unmetered false air and pressure standing waves. Verify continuity (< 0.5 Ω) on the signal wire between the component plug and the ECM header connector. Verify loaded supply voltage and harness terminal pins at Cylinder 2 Fuel Injector. Check circuit continuity and ground-side voltage drop (< 0.05 V) for Cylinder 2 Fuel Injector. Perform fuel rail pressure-drop / balance test to identify leaking, stuck, or clogged injectors. Mechanic tip: Pro-tip for cylinder 2: Intake manifold runner geometry exposes cylinders 2 and 3 to distinct pressure pulsation waves. Smoke test the intake runner seals thoroughly.

Related:Cylinder 2 Fuel Injector, Wiring harness and connectors, Control Module (ECM/PCM)

System

Powertrain (Engine & Gearbox)

Technical Description

The control module has detected a fault in the Cylinder 2 Fuel Injector (P0202). The module sees no circuit at all — broken wire, backed-out pin, or a failed sensor. The fault is isolated to cylinder 2, positioned on the inner block section with asymmetric intake runner pulses. This directly impacts individual cylinder volumetric efficiency, firing synchronization, and dedicated harness branch loading.

Multimeter Test Points & Nominal Values

Test Point / Component	Measurement	Nominal Target Range	Test Condition
Cylinder 2 Injector – Coil Resistance	Resistance (Ω)	11.5 - 15.5 Ω (port) / 0.5 - 3.0 Ω (direct injection)	Connector disconnected at 20°C (cylinder 2)
Cylinder 2 Injector – Injection Pulse at 180° crank angle	Signal (ms)	2.5 - 4.5 ms idle / 1.5 - 20 ms under load	Engine running
Cylinder 2 Injector – Supply Voltage	Voltage (V)	11.8 - 14.4 V (port) / up to 65 - 90 V boost (direct)	Ignition ON / engine running

Cylinder 2 Injector – Coil ResistanceResistance (Ω)

Nominal Target:11.5 - 15.5 Ω (port) / 0.5 - 3.0 Ω (direct injection)

Connector disconnected at 20°C (cylinder 2)

Cylinder 2 Injector – Injection Pulse at 180° crank angleSignal (ms)

Nominal Target:2.5 - 4.5 ms idle / 1.5 - 20 ms under load

Engine running

Cylinder 2 Injector – Supply VoltageVoltage (V)

Nominal Target:11.8 - 14.4 V (port) / up to 65 - 90 V boost (direct)

Ignition ON / engine running

Oscilloscope Waveform Analysis

1 ms/div, 20 V/div

Scope the control side for Cylinder 2 Injector. The trace must show pull-down to < 0.2 V at open, flat saturation, and an inductive spike (40 - 90 V) phase-offset to 180° crank angle.

Possible Causes

Open circuit, damaged wiring harness, or disconnected plug at Cylinder 2 Fuel Injector

Mid-block harness fatigue (cylinder 2): Wiring friction against valve cover bracket and hydraulic standing pressure waves in fuel rail between cylinder 1 and 2.

Asymmetric intake tumble:Tumble airflow disruption and localized carbon deposits on intake valves of cylinder 2.

Channel A:Verify dedicated wiring pins and signal pair for circuit A against the schematic.

Chafed or pinched wiring harness along the signal path to Cylinder 2 Fuel Injector

Internal mechanical wear or carbon deposits inside Cylinder 2 Fuel Injector

Defective internal output driver or reference circuit in the control module for Cylinder 2 Fuel Injector