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SoCal Driver SoCal Driver is offline
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Join Date: Feb 2002
Location: Costa Mesa
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As I understand the logic; the speed sensor is what keeps the fuel pump running. But, there is an over ride when you are cranking the car. The signal to the starter is split off to the DME. The DME will close the fuel pump contacts in the DME relay. These contacts can only close if the first set of contacts are closed. We know the first set are closed because you report 12 vdc at the injectors.

The reference sensor is what fires the coil and the injectors. If you have spark you should also be seeing injector pulses. Do you? If you have spark and no injector pulses then I would be suspicious of the DME and/or the wiring from the DME to the injectors.

If you take the injectors out and lay them on some rags and crank the engine you should see them spray. Don't get carried away.

The AFS may keep the injectors from firing if it's not reading right. The temp sensors regulate the injectors but I don't think they stop them completely.

The throttle switch can stop the injectors if set wrong.

Too many beers can give you a head ache.
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Hugh - So Cal 83 944 Driver Person
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Old 04-12-2004, 02:40 PM
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