If a fuel injector measures 0 ohms resistance when checked with a multimeter, it usually means the injector has an internal short circuit the coil inside the injector is shorted.
What It Means Electrically:
- A normal injector has some resistance because of the coil wire inside.
- 0 ohms = short circuit, meaning the coil is bypassed or internally damaged.
What this means:
- Normally, fuel injectors have a certain specified resistance, depending on their type:
- Low-resistance injectors (“peak and hold”) are typically around 2–5 ohms.
- High-resistance injectors (“saturated”) are usually around 12–16 ohms or higher.
What Happens as a Result:
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Excessive current draw:
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The injector will try to pull much more current than designed.
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This can overload the injector driver circuit in the ECU (engine computer).
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Possible ECU or fuse damage:
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The injector control circuit might blow a fuse or burn out a transistor or driver inside the ECU.
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Injector won’t function properly:
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It may not open or close correctly, leading to:
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No fuel delivery to that cylinder.
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Or uncontrolled fuel spray (if it’s stuck open), causing:
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Rich mixture.
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Misfires.
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Engine flooding.
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Engine performance issues:
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Rough idle.
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Poor fuel economy.
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Potential for engine damage (from fuel wash-down or misfiring).
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What to Do:
- When the resistance is 0 ohms, it’s like the injector coil wire is completely bypassed (no resistance at all), indicating that:
- The coil may have burned and fused together.
- The internal insulation failed.
- The injector is bad and needs to be replaced.
Important: Always check the manufacturer’s spec for what the injector resistance should be, but 0 ohms is definitely not normal for any injector.