Cylinder 4 Injector Circuit Range/Performance
The P02F1 code indicates that the Engine Control Module (ECM) has detected an issue with the electrical circuit or performance of the fuel injector on cylinder 4. This could be due to a faulty injector, wiring problems, or a malfunctioning driver circuit in the ECM. The injector may be stuck open, closed, or not receiving the correct voltage/current, leading to improper fuel delivery and combustion issues.
01. Most Common Causes
- Faulty fuel injector on cylinder 4
- Open or shorted wiring in injector circuit
- Corroded or damaged connector at injector
- Failed ECM injector driver
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire on cylinder 4
- Rough idle or poor acceleration
- Decreased fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect injector connector and wiring for damage.
Step 3: Use a multimeter to test injector resistance (typically 11-18 ohms).
Step 4: Perform a power balance test to confirm cylinder 4 misfire.
Step 5: Check injector pulse with a noid light or oscilloscope.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause catalytic converter damage due to unburned fuel.
How much does it cost to fix?▼
Replacing a single injector typically costs $150-$400 including parts and labor.