Fuel Injector Leak Detected (Cyl 1)
Indicates a fuel injector leak in cylinder 1.
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What it means (plain English)
The engine control module (ECM) is detecting that the fuel injector for cylinder 1 is leaking fuel, which can cause poor engine performance and damage if not addressed.
What the computer is actually seeing
The ECM monitors fuel rail pressure and injector operation times. If the pressure drops below 200 kPa or the injector opening time exceeds expected values significantly, it flags a leak.
What a healthy reading looks like
Expected rail pressure during operation is typically between 240-300 kPa; injector opening times should be around 2-10 milliseconds under normal conditions.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the wiring and connector at the fuel injector for cylinder 1. Look for corrosion or damage.
- 22. Perform a visual inspection of the injector O-rings and seals for cracks or leaks.
- 33. With the engine running, use a fuel pressure gauge to monitor rail pressure. It should stay above 240 kPa. If it drops, suspect a leak.
- 44. Disconnect the fuel injector for cylinder 1 and perform a resistance test. It should be between 12-16 ohms. If out of spec, replace the injector.
- 55. If all checks are good, use a scan tool to compare injector pulse widths against other cylinders. A significant deviation (greater than 20%) could indicate a problem with the ECM or calibration.
Common causes
- Faulty fuel injector
- Damaged O-rings or seals on injector
- Contaminated fuel
- ECM software issue
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, it's not safe. A leaking injector can cause engine damage and increase emissions.
Will this code come back after repair?
If repaired correctly, it should not come back unless there are underlying issues.
Why does this code pair with SPN 2385?
SPN 2385 indicates a leak in cylinder 2, indicating a potential broader issue with the fuel system.
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