Fuel, spark, good injectors. Wont start (runs with carb cleaner)

Tiny
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Looks like the none power wire has a partial ground somewhere. Unplug the computer and see if that ground is still there?
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Sunday, August 12th, 2012 AT 11:13 PM
Tiny
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Is the computer under the dash?
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Sunday, August 12th, 2012 AT 11:29 PM
Tiny
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Its C1 in the diagram I posted.
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Sunday, August 12th, 2012 AT 11:47 PM
Tiny
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Now I have no voltage across the connector, no ground on non power side, no continuity on non power side. So does that mean the computer is bad?
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Monday, August 13th, 2012 AT 12:30 AM
Tiny
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I still have 12v on the power side of the connector.
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Monday, August 13th, 2012 AT 12:30 AM
Tiny
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The dark blue wire should only have a ground when the computer is plusing the injectors. So if there is a partial ground on the dark blue wire sounds like the injector driver in the computer is bad and partially shorted to ground. Now with the computer still unplugged see what the dark blue wire reads to ground ohms value at the injector harness?Also do the same thing with the key in the off position and the computer plugged in?
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Monday, August 13th, 2012 AT 12:42 AM
Tiny
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Blue connector to ground no reading key off computer unplugged. Key off computer attached about 20 ohms. Also checked ohms across power side to blue wire computer plugged in key off reads about 4 ohms.
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Monday, August 13th, 2012 AT 12:52 AM
Tiny
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It looks like a bad computer.
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Monday, August 13th, 2012 AT 2:53 AM
Tiny
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1. If I replace this with a scrap yard computer, will I have to get someone to do programming on it?
2. Is there any way to bench test the computer to be certain?
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Monday, August 13th, 2012 AT 10:53 AM
Tiny
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There is really no way to bench test it but there should be no ground to that non power control wire unless the computer is commanding the injector open. Also if you get the correct computer used there should be little to no programing.
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Wednesday, August 15th, 2012 AT 3:29 AM
Tiny
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I really appreciate all the help
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Wednesday, August 15th, 2012 AT 5:56 PM
Tiny
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Your welcome thats what were here for when you unplugged the computer we know the wire wasnt shorted to ground somewhere. So that leaves the computer.
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Wednesday, August 15th, 2012 AT 6:34 PM
Tiny
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I replaced the ECM and switched over my prom. The car still wont start. The readings did change - I no longer have the short to ground on the injector wires. However, noid light still not flashing, has spark, has good fuel pressure, does run on carb cleaner. I took a guess at throttle position sensor and changed it but still no start.
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Monday, September 10th, 2012 AT 5:01 PM
Tiny
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So do we have power to the injector connector with the key in the run position?
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Monday, September 10th, 2012 AT 7:04 PM
Tiny
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Yes, there is power.
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Monday, September 10th, 2012 AT 8:04 PM
Tiny
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So I take it the other wire doesn't pluse ground?
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Monday, September 10th, 2012 AT 8:16 PM
Tiny
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Correct
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Monday, September 10th, 2012 AT 8:48 PM
Tiny
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Did you ohms check the ground plusing wire?Also any codes in the computer?
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Monday, September 10th, 2012 AT 9:28 PM
Tiny
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Ohms ground pulse wire to chassis was a full reading. I dont remember what scale I had it on but it buried the needle. I don't know I can get codes out of the computer - it's an OBD1. Is there a way?
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Tuesday, September 11th, 2012 AT 1:29 AM
Tiny
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Can you get a ground pluse signal right out of the computer?
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Tuesday, September 11th, 2012 AT 1:40 AM

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