Help with #8

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Apr 29, 2011 | 11:12 PM

grizzweideman

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Help with #8

Hello I have replaced #8 injector 3 different times then on the 4th time i replaced the valve cover gasket and harness and it is still running bad and the mechanic did a buzz test on it before and after and the tester said that #8 is not getting any power could the truck computer be the problem. I can`t figure it out so any help would be grate thanks. Its a 1999 super duty 7.3

Apr 29, 2011 | 11:28 PM

woodnthings

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From: Snohomish, WA

The IDM supplies the signal to the injector. It could be bad, or you may have abad wire between the IDM and the injector. Since you changed the UVCH, it is more than likely not that. You should be able to ohm out the wire from the IDM connector to the connector at the valve cover gasket. That will give you an idea if it is wiring or something else.

Have you swapped #6 & #8 around to make sure it is not an injector?

Attached is a PDF for you on the diagram.

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2001F_PCM-Engine_Diagram.pdf (786.8 KB, 126 views)

Apr 30, 2011 | 06:36 AM

CPUNeck

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From: Fort Campbell, KY

Quote:

Originally Posted by grizzweideman

Here's another thought, the wire loom that runs across your D/S valve cover has all your engine wiring in it. Very common for the wires on the bottom side of that loom to chafe on the valve cover. You just never know which ones it will be.

I'd disconntect that big connector on top of the valve cover (10mm socket), then take a good look inside, where the harness touches the valve cover, to see if there is damage to any wires. Note too, just because the jacket isn't worn through, doesn't mean the wire's ok. I you see wear on the wire jacket, it will be suspect (the strands on the inside can break also)

Apr 30, 2011 | 07:07 AM

trike1946

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From: NJ where fun comes to die

A gray CPS was causing my #8 to seem dead. The fix was done in the computer after I went to a black one. No idea what they did to fix it. It was my 01 F350.

Apr 30, 2011 | 09:41 AM

grizzweideman

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No I did not swap #6 with #8 I was afraid to I thought that #8 injector was a tuned injector or so i was told but ill go and took at the wire. What is a (CPS)?
Thanks for the help.

Apr 30, 2011 | 09:51 AM

Ponyboychris

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Joined: Jan 2007

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From: Kiowa CO

CPS= Cam Position Sensor. Big failure item on these trucks. There's been recalls by Ford to address the issue. The original CPS's were black in color and they would die without notice. The recall CPS's are grey and supposedly were a fix to the sudden failure but some members have noticed performance issues related to them.

Apr 30, 2011 | 09:51 AM

grizzweideman

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No I did not swap #6 with #8 I was tolled that #8 was just for that cylinder. Thanks for the wiring diagram ill take a look and what is a ( CPS )?
Thanks for the help.

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Apr 30, 2011 | 11:48 AM

woodnthings

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From: Snohomish, WA

A CPS will usually just quit, not have an issue with one cylinder. The big issue that the CPS causes on #8 is code P0284. From what you describe, you are failing the Buzz test too. That is specific to the IDM, Wiring, or Injector.

Your injectors should all be the same on your '99. The later years do have a different injector in #8. It is an AE injector while 1-7 have AD's. It is considered a long lead injector or LL. It is obvious when you look at it.

Apr 30, 2011 | 02:44 PM

#10

grizzweideman

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I got the injector form ford so I don`t think that it`s the injector iv been through 4 different injectors and the outcome is the same the only other thing it could be is the (IDM) ill go check and let you know.
Thanks for the help