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John_AZ John_AZ is offline
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Join Date: Jul 2001
Location: ~Carefree Highway~
Posts: 5,833
Quote:
Originally Posted by alfadoc View Post
Here is the big clue. A major circuit that is controlled by the ignition switch is not getting energized. Your mechanic has a wiring diagram for the car, right? Otherwise, it's like throwing darts at a board blindfolded (darts=expensive Porsche parts).

Start with a circuit diagram for the ignition switch. Make sure that the wires that are supposed to be energized when the switch is on are indeed being energized. Start at the back of the ignition switch and move forward, component by component, following the wiring diagram. Eventually you'll find the place where power is going in, but not coming out. That's how you perform electrical diagnosis.
Good stuff alfadoc.

Zarbuck,
You might want to buy a NOID light to test the signal to the injectors.

WILMAR BOSCH PFI FUEL INJECTION NOID TEST LIGHT W85102 | eBay

To add to alfadoc, here is a simplified sequence of events to start a car.



Remember also that when cranking, the tach needle has to jump 1/16th inch to send a signal to the DME.

GL
John
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Old 08-30-2011, 05:27 PM
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