96 F350 skipping

Brandon hill

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My truck is running rough and has no power. Replaced valve cover gaskets pigtails oil and filter fuel filter oil pressure sensor thing that is on top of the motor idm and its still skipping just like it was before. Valve cover gasket was melted on the passenger side is the reason I replaced the valve cover gaskets. Hooked scanner up did a buzz test all 8 injectors buzz loud. But the hold passenger side injectors are not working only running on drivers side. Codes say short to ground low battery voltage injector open and so on. Anybody know what my problem could be? Thanks in advance!
 
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Hopefully you did the external pigtails one wire at a time to ensure that the order remained the same. Break out the multimeter and try this:

For checking the injector/glowplug wiring: From each valvecover gasket connection's outermost pins (2 per connector) to ground you should get 0.1 to 2 ohms (indicates good plug and wiring). From each valvecover gasket connection's center pin to each immediately adjacent pin, you should get around 3 ohms (indicates good injector solenoid and wiring). You should not get any continuity from any of the outer pins to the 3 inner pins (indicates no shorts between injector and glowplug wiring). You should also get 0 to 1 ohms from each of the external harness connectors outer pins back to the Glowplug Relay's large terminal on the GP side (indicates good wiring from external connections back to the relay).

Other than that, you might need to check the wiring from the IDM connector back to the external VC plugs. Cheers!
 

Brandon hill

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Yes there wired correctly. where does that side ground at? Cause the scanner is saying bad ground and I'm not good with a meter I'll have to get somebody to do it. Took it to a shop and my bill is already 600 bucks and they haven't fixed the problem one bit
 

Brandon hill

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Somebody please help me out!! I need my truck back running right. Do yall think a new engine harness would solve my problem?
 

Bugman

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Here is a test for the wiring from the IDM to the injectors just to make sure that all the wiring is correct. Other than that you may need to get a scanner on it to see what it is doing.
 

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Brandon hill

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It's just throwing codes for the whole passenger side of the engine. Injector open low battery voltage and short to ground and thanks for replying
 

Bugman

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One bad injector on the passenger side will cause the IDM to shut down all 4 on that side.
 

Bugman

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I should of also added that a ground fault on one of the injector wires will also cause the same thing.
 

Brandon hill

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If a injector was bad I thought it would just skip on the one that was bad? And would bad injector throw all those codes? I'm leaning more towards a wiring issue I hope atleast
 

Brandon hill

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And the reason I say that is because when I replaced the valve cover gasket on the side that was burnt I started the truck and it run good just had a very small skip to it so I went ahead and replaced the other side and that's when it went back to skipping bad like before. If it was an injector I don't think it would have ran that good then changed when I replaced the other one
 

79jasper

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"Oil pressure sensor thing that is on top of the motor" = ICP sensor.
Where'd you buy it? Try unplugging it.
I know you didn't state a code related to the HPO SYSTEM, but you never know.

Sent from my SM-T537R4 using Tapatalk
 

Bugman

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Bought it at the ford place ran me 200 bucks. And how do you tell if the cps is bad?

With what you said in a previous post I doubt that it is the CPS:
It's just throwing codes for the whole passenger side of the engine. Injector open low battery voltage and short to ground and thanks for replying

Did you look at the IDM wiring test that I posted for you? If you are getting a short to ground and a injector open code when you scan it that test may isolate it for you.
 
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Well, now is the time to get better at it! One bank down does not usually indicate a CPS problem. Since you have swapped IDMs with the same results, I would do those tests just to verify no wiring problems from end to end. Cheers!
 
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