Injector not working
#1
06-24-2016, 01:57 PM
Injector not working
I have a 99 f150 4.6
I get trouble code for misfiring, i have good spark and fuel, but truck can barely run, its shutting off. It has 4 injector thats not pulsing, i change them 4 its the same. The truck is running on 4 injector. 3 on driver side not working and 1 on other.Need help
I get trouble code for misfiring, i have good spark and fuel, but truck can barely run, its shutting off. It has 4 injector thats not pulsing, i change them 4 its the same. The truck is running on 4 injector. 3 on driver side not working and 1 on other.Need help
Last edited by Agiz; 06-24-2016 at 02:00 PM.
#2
06-24-2016, 11:39 PM
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#3
06-24-2016, 11:46 PM
Yah, i change the injectors. I have tested the connector, there is positive power, and negative. Maybe its not getting signal to fire. Can i connect and piggyback off the one thats working. I mean can i connect a wire to the one thats getting signal to the one not. Im desperate here
#4
06-25-2016, 12:54 AM
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i don't think you should do that, but if you put the one that works in the place of one that does not, and move the one that doesn't where the working one was. Follow me? If the problem stays in the same spot, it's the connection (electric or fuel). If the problem follows the "bad" injector it's the injector.
Are the fuses all good? Have you checked them?
Are the fuses all good? Have you checked them?
#5
06-26-2016, 11:24 PM
Fuel injectors fire in the same order as the spark plugs but earlier in time when the intake valve is open before compression takes place.
This is why you can't change things around for a test..
They have 8 separate injector drivers in the computer that supplies a ground.
What you need to do is look for the ground from the computer to be applied each time the injector is to inject fuel.
Use either a voltmeter or a device called a NOID light.
Use a voltmeter because the injector has voltage standing on it full time.
You would see the pulses as the meter dipping toward zero when the ground was applied.
If those grounds are missing, either the harness is open or the computer has faulty drivers and would need to be replaced.
A further test if the drivers as suspected of being faulty is to use an Ohm meter to look back at the drivers in the computer for resistance.
If you see very high or an open or a low value like a short, it's likely they are damages.
A reading for about 10,000 ohm +\- is about correct.
No shorts or opens.
Good luck.
This is why you can't change things around for a test..
They have 8 separate injector drivers in the computer that supplies a ground.
What you need to do is look for the ground from the computer to be applied each time the injector is to inject fuel.
Use either a voltmeter or a device called a NOID light.
Use a voltmeter because the injector has voltage standing on it full time.
You would see the pulses as the meter dipping toward zero when the ground was applied.
If those grounds are missing, either the harness is open or the computer has faulty drivers and would need to be replaced.
A further test if the drivers as suspected of being faulty is to use an Ohm meter to look back at the drivers in the computer for resistance.
If you see very high or an open or a low value like a short, it's likely they are damages.
A reading for about 10,000 ohm +\- is about correct.
No shorts or opens.
Good luck.