Injector Circuit Low Cylinder 1
The P0261 code indicates that the powertrain control module (PCM) has detected a low voltage or current condition in the electrical circuit for the fuel injector on cylinder 1. This typically means the injector circuit has lower than expected resistance, possibly due to a short to ground, a faulty injector, or wiring issues. This can cause a misfire, reduced engine performance, and increased emissions.
01. Most Common Causes
- Faulty fuel injector on cylinder 1 (internal short)
- Short to ground in the injector wiring or connector
- Damaged injector driver circuit in the PCM
- Corroded or loose electrical connector at the injector
02. Symptoms You Will Notice
- Engine misfire or rough idle
- Check Engine Light illuminated
- Reduced engine power and poor acceleration
- Increased fuel consumption and emissions
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm the code and check for related codes.
Step 2: Visually inspect the injector connector and wiring for damage, corrosion, or shorts.
Step 3: Measure resistance across the injector terminals; compare to manufacturer specs (typically 12-16 ohms).
Step 4: Check for voltage at the injector connector with the key on; should see battery voltage on one pin.
Step 5: If wiring and injector are good, test the PCM injector driver circuit or replace the PCM.
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 the misfire can damage the catalytic converter and cause poor performance. Short trips to a repair shop are acceptable.
How much does it cost to fix?▼
The typical repair cost ranges from $50 to $150 for diagnosis and injector replacement, but can be higher if the PCM needs replacement.