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How to test injectors

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Old Feb 18, 2017 | 05:29 PM
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Default How to test injectors

How should I test to see if my injectors are getting power? I have a rough running condition and checked it with a code reader. The code reader said it is a injector issue (low pressure, clogged or non functioning).But it did not say witch one. I know I can get a noid light but I'd like to use my multi-meter if I can.
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Old Feb 18, 2017 | 05:31 PM
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BTW it ran fine until yesterday.
There is 65 lbs. of fuel pressure to the fuel rails.
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Old Feb 19, 2017 | 07:41 AM
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What code is the reader showing?
Multi meter will check for 12v power.
Won't do well to check pulsing... Too slow to respond.
A noid lite is cheap.
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Old Feb 19, 2017 | 09:58 AM
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Default Fuel Injector Power/Ground

Hi Cody, the answer is GOOD tech for All.
The fuel injector is powered by 12 volts with key "on".
The EMS allows the injector internal coil a Ground return path.
When this takes place, an electromagnet is created "lifting" the pintle.
The fuel then flows through an orifice, the flow restrictor, past the dust cap into the port/cylinder.

The Fluke Meter I use IS be BETTER than a "noid" light.
The 12 volt supply can be accurately measured.
The Duty Cycle can be measured when the engine is in operation.
The injector impedance can be measured.
When the engine is in operation you can see the speed of each injector and compare it with the other seven.

This type of measurement is the SAME as the EMS's internal injector driver control IC "see's", then sets the IM light when incorrect.

Lance
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Old Feb 19, 2017 | 10:08 AM
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The injector might have a plugged screen.

Pull them all and have them cleaned if the fuel pressure is correct.
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Old Feb 19, 2017 | 11:07 AM
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Thanks for the info guys. This morning I went to my local parts store and rented a set of noid lights. All 4 on the drivers side were out. Turns out that the painless harness has one fuse per side and it was blown. I would have bet money it was only missing on one cylinder. Replaced the fuse and it runs great. Now I have to figure out why that fuse blew.

Thanks again guys. I'm still kinda new to injection systems and electronics, but I am learning.
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Old Feb 19, 2017 | 11:13 AM
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di·ag·no·sis
ˌdīəɡˈnōsəs/
noun
1.
the identification of the nature of an illness or other problem by examination of the symptoms.
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Old Feb 19, 2017 | 12:12 PM
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I hate electronic stuff mostly because I grew up with carburetors and distributors but this code scanner is pretty cool.
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