Fuel Injector 4 - Electric Fault
Indicates an electrical issue with Fuel Injector 4.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The fuel injector for cylinder 4 isn't getting the right electrical signal to operate, meaning that cylinder 4 isn't getting fuel properly, affecting engine performance.
What the computer is actually seeing
The engine control module (ECM) monitors the voltage and current to Fuel Injector 4. When it detects that the voltage is outside the expected range, it sets this fault code.
What a healthy reading looks like
Expected injector voltage should be around 12-14 volts with a peak current of approximately 1-2 amps during operation.
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 connectors to Fuel Injector 4 for any signs of damage or corrosion. Repair if necessary. Decision: If repaired, clear the code and test drive. If the code returns, continue.
- 22. Measure voltage at the injector connector with the engine running. You should see 12-14 volts. Decision: If voltage is within range, continue. If not, check the wiring from the ECM to the injector.
- 33. Check the ground connection for the injector. Ensure it has good continuity. Decision: If the ground is bad, repair it and retest. If good, continue.
- 44. Swap Fuel Injector 4 with another cylinder injector to see if the code follows the injector. Decision: If the code changes to the new cylinder, replace the injector. If not, continue.
- 55. Inspect the ECM and its injector driver circuit for faults with the manufacturer's service manual. Perform any necessary replacements or repairs.
Common causes
- Wiring harness issue (frayed or damaged wires)
- Faulty fuel injector
- Bad ECM or injector driver circuit
- Poor connector contact or corrosion
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, it's not safe to drive as the affected cylinder won't be firing correctly, impacting power and potentially damaging the engine further.
Will this code come back after clearing?
If the underlying problem isn't fixed, yes, the code will likely return.
Can this code pair with other codes?
Yes, it can appear alongside other injector-related fault codes, indicating a wider issue with fuel delivery.
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