1999 Saab 9-3 repair Question No Voltage at the Fuel Injecto

1999 SAAB 9-3
134,000 MILES • 4 CYL • 2WD • AUTOMATIC
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HP
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I parked my car at my driveway and went on Vacation for 4 days. After my Vacation I try to start the Engine in the morning and the Starter turned but no Ignition.
I check everything out and found no Voltage to the Fuel Injectors.
I changed the Crankshaft Position sensor and have also Sparks. It will run on independent fuel source
I don't know what controls the Injectors. Is it the ECU or the twice system?
Jun 16, 2009 at 9:02 AM
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DOCFIXIT
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Hi
Injectors power from ignition discharge module on valve cover green/red wire. Ground is provided by computer.
Hope this helps
Thanks for donate
Jun 16, 2009 at 1:53 PM
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HP
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I think the ECU controls the injection on a Saab?
Jun 16, 2009 at 1:57 PM
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DOCFIXIT
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That's what I said ground controled by ECU ie. computer. Power come from module
Jun 16, 2009 at 2:01 PM
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HP
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Ignition Module works
I dont have ground from ECU
Jun 16, 2009 at 2:13 PM
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DOCFIXIT
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Check green/red wire coming out of Ign Dis Module it supplies power to injectors. If you have power and no ground then ECU is possibly faulty.
I'm confused your post started no power know no ground. Let me know
Jun 16, 2009 at 3:54 PM
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HP
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Green/red wire is OK
Sorry for the confusion, but that's the details I needed.
I have all grounds missing from the ECU
I will replace the ECU
I let you know
Jun 17, 2009 at 7:23 AM
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DOCFIXIT
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Good luck and yes let me know
Jun 17, 2009 at 9:12 AM
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HP
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I forgot to ask!
Voltage from green /red wire is pulsing
Is this correct?
Jun 17, 2009 at 9:27 AM
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DOCFIXIT
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Are you checking at injector terminal? if yes then ECU must be grounding the pulses indicate injector on/off. Can you feel or hear injector click? Can you get a noid light hook up will tell if ECU is firing injector
Jun 17, 2009 at 10:28 AM
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HP
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Car is running again.
Bad ECU
Bad Ignition Cassette (Orange Sparks)
Bad fuel pump
All at the same time!

Thanks for your help!

Hp
Jul 1, 2009 at 8:08 AM
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DOCFIXIT
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I have never seen so much stuff go out at once. No wonder you where having such a time diagnosing.
Glad it is running. Thanks for letting me know
Jul 1, 2009 at 11:28 AM
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MNTHNY4
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i did not see where you did a fuel pressure test ,to find out if fuel pump is working or not ,plus check relays located under the d/s dash panel ,just below where dice unit is located ,saab ecm do not go that easy ,& saab system is all about power to grounds so do not mess with it if u do not understand it ,check basic system first ,do not get all technical ,saab's are expensive to repair if u blow the ecm module .
Aug 29, 2009 at 8:17 PM
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