I'm not an auto-electrician, but believe that fuel injectors are relatively simple solenoid valves.
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so wouldn't expect the wires being the wrong way round to have any effect.
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But having said that, I just took out a set of Weber injectors I have lying about, and they have
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+ and
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- on them.
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Anyway, they're generally triggered on the earth side, so if the insulation is frayed and the cable manages to touch almost any part of the chassis, the effect will be to open the solenoid.
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Elsewhere, people have seen gross overfuelling as a result.
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Swap em round.
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If the fault jumps to the other cylinder, it must be the injector, otherwise, suspect the wiring.
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