Injectors 5-8 not firing
08-08-2010, 03:07 AM
#1
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Injectors 5-8 not firing I noticed a loss of power a couple days ago so I started troubleshooting. I found that the rear 4 cylinders (5-8) were not firing or firing intermittently by feeling the primaries. This is what I have done as far as troubleshooting so far:
1) Pull plug and checked for spark. Hooked up plug to all coil packs to make sure it fires. All coils have spark.
2) Replaced plugs on non-firing cylinders.
3) Swapped non-firing cylinder injectors with firing cylinder injectors
4) Swapped plug wires.
5) Swapped coil packs from ds->ps
6) Swapped PCM
I tried to check voltage at injector connections, but my multimeter can not read such short pulses ($250 Fluke meter). I believe that this is an electrical problem at the injector connection. Is there any good way of testing this to see if this is my problem? Is there any way that the pinouts on the PCM connector could be loose (haven't looked at this yet)?
1) Pull plug and checked for spark. Hooked up plug to all coil packs to make sure it fires. All coils have spark.
2) Replaced plugs on non-firing cylinders.
3) Swapped non-firing cylinder injectors with firing cylinder injectors
4) Swapped plug wires.
5) Swapped coil packs from ds->ps
6) Swapped PCM
I tried to check voltage at injector connections, but my multimeter can not read such short pulses ($250 Fluke meter). I believe that this is an electrical problem at the injector connection. Is there any good way of testing this to see if this is my problem? Is there any way that the pinouts on the PCM connector could be loose (haven't looked at this yet)?
08-08-2010, 06:06 PM
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Note I am running E85 and am only half way through my first tank. My injectors are big enough to be running E85.
I have changed my fuel filter as well.
Just now I unplugged the connectors for the injectors on cylinders 1-4. Now cylinders 5-7 are firing, but cylinder 8 is firing intermittently.
I have stock fuel rails. I have checked to make sure they were not plugged. Can the fuel rail be the root of my problem?
I have changed my fuel filter as well.
Just now I unplugged the connectors for the injectors on cylinders 1-4. Now cylinders 5-7 are firing, but cylinder 8 is firing intermittently.
I have stock fuel rails. I have checked to make sure they were not plugged. Can the fuel rail be the root of my problem?
08-08-2010, 11:42 PM
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I used the node tester. All injectors are getting power.
So now I removed the valve cover to make sure the the valves were opening and the cam wasn't flat. All was good
The only thing that I can think of is the fuel rail or regulator.
Anyone have any ideas?
So now I removed the valve cover to make sure the the valves were opening and the cam wasn't flat. All was good
The only thing that I can think of is the fuel rail or regulator.
Anyone have any ideas?
08-13-2010, 10:18 AM
#6
Maybe something got in your fuel rail and clogged your injectors?? If they have power then they should be firing. Right? So everything is happening like its supposed to. Injector receives power, intake valve opens, but still no fuel. That would be my guess. Have you tried replacing your fuel rail? Did the injectors you swapped work after you swapped them?
