Question about 1991 Chevrolet Camaro

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No run problem

With the key turned on i have power to both sides of the injectors.where should i look for the problem.

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  • radv6 Sep 03, 2008

    it was a shorted injector.changed it and fixed the problem.



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If the organization is as in most cars, the injectors ae controlled by individual transistors located in the ECM/ECU (computer).

Since the injectors are controlled by pulse action from there, having voltage on both sides of the leads is normal I would say if the engine is not running.
The typical arrangment is that one side of the injector coil is supplied with 12V if the ignition is turned on and the other side of the coil is grounded under control of the computer but only for a few milliseconds at a time, nothing that you can measure with a meter.
If you were monitoring the low side of an injector with a meter, you might see a slight decrease in the reading but that's all.
If even that small decrease is not present, then the computer has probably failed and it is no longer grounding each injector when required.

Posted on Sep 02, 2008


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Could be your injector circuit is the problem. Check if injectors have power to them with key in on, not start. Each injector has a common hot wire and a ground that goes into the computer for internally grounding the injector circuit, and consequent pulsing of the injectors. There should also be an injector fuse, so check that if circuit has no power to the injectors.
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