1991 Chevy S-10 fuel issue

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REDDOG46406
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Engine Performance problem
1991 Chevy S-10 4 cyl Two Wheel Drive Manual

i have changed the fuel pump the fuel filter the fuel injector the pressure reg and relays. i am getting fuel to the injector but the truck still wont start unless i put a little fuel in the throtle body but then it dies. any ideas of what i should try next.
Jul 17, 2010 at 2:44 AM
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PEAR69
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Check for voltage at the injector. With the key on (engine off) you should have 12 volts on one wire at the injector -- (or one wire at each injector if there are two injectors)... The other wire is a ground that goes to the ECM (computer). The ECM fires the injector by applying a ground to the injector..
If there is no voltage, check for a blown fuse..
Jul 17, 2010 at 4:34 AM
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REDDOG46406
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[quote:35188fc2af="pear69"]Check for voltage at the injector. With the key on (engine off) you should have 12 volts on one wire at the injector -- (or one wire at each injector if there are two injectors)... The other wire is a ground that goes to the ECM (computer). The ECM fires the injector by applying a ground to the injector..
If there is no voltage, check for a blown fuse..[/quote:35188fc2af]
i have 12 volts at the connector
Jul 17, 2010 at 6:17 AM
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PEAR69
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Now you must determine if the injector is receiving a ground signal from the ECU - This fires the injector. You should use a NOID light. This is a little device that plugs into the injector electrical connector. When you crank the engine the noid light will blink -- this indicates two things -1. there is voltage and 2. there is a ground from the ECU...If the noid light does not blink then there is a problem with the ground to the ECU -- or (worst case) a bad ECU...
You can do this test with a regular 12 volt test light - but you can damage the electrical connector or over load the circuit if you are not carefull -- I believe Autozone or places like that will loan you a noid light for this test...
Jul 17, 2010 at 2:55 PM
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