Cam position sensor

501 96 7.3

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I need a little help please. Truck in signature, truck ran flawlessly for years. Last problem was cps 4 years ago. Same symptoms now, got a dtc for the cps, rough idle, low on power. You know cps issues. Put a parts store black and grey and also a ford gray one, all same results. Took chip out to rule it out. 600 icp at idle, 65psi fuel, no more codes, out of ideas.

Any way to check wiring of cps, one wire seems grounded, if I knew where other two went I could ohm them out.
 

501 96 7.3

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Ok so I ohmed the three wires back to the big square block on fender. All good. Also passed buzz test.
 

501 96 7.3

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Ok put my riff raff 3” plenum inserts in I’ve had for a few years. Ohmed drivers side injector wiring back to 42 plug connector, 3.2 was the highest reading...what next? Other side on ohming injector wiring?
 

501 96 7.3

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I will have to put everything back together and go for a drive, I don't remember what high pressure oil was doing. Do you think the hpop may be giving up?

I am a bit confused on the 42 pin connector. I was getting continuity from injector wiring to more than one pin on the connector. Do they share a ground or something?
 
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On the 42-pin connector, if the connector is unplugged and the injector wiring is unplugged (all of them), you should not get continuity at more than one pin on the 42-pin connector. You can get continuity from a the injector common pin (pin 11 for one side and pin 12 on the other) to the injector commons on each bank (middle pin on the VC harness connectors). Cheers!
 

501 96 7.3

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Thanks for the replies all. I think I will have to redo the continuity test, some of the injectors were still plugged in.
 

501 96 7.3

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I was checking for codes often while driving, only had the cps code once. No other codes, frustrating.
 

501 96 7.3

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So i redid the continuity test to 42 pin connector and injector wiring, with all the injectors unplugged, .4 ohms was the highest reading. I am going to put valve covers back on unless there is anything else to check while I am in there? I am not sure what to check next. I did start it this morning, it built 1200 psi on the high pressure oil, still running rough. Also verified it has oil. I may try to shim the cps, I did some reading on that last night.
 

ghohouston

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CPS codes can be triggered by continuous cranking without starting as well. I fought my 97 for some time before I figured out my fuel tank selector valve failed, BETWEEN positions 3 hours from home. It would idle alright, 1st and 2nd gear were okay, but 3rd and beyond, it would fall on its face and die. This was with e fuel as well.
 

501 96 7.3

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Magnum, the hp oil could be a problem I guess but I will have to get it back together and go for a drive to monitor oil pressure. And as you said already that would throw a code.?

gohouston, I assume since it has 60-65 psi fuel that would rule fuel out as a problem. My truck sputters, runs rough at idle and through the entire rpm range. I do have a regulated return with Efuel. I burnt one pump up because of low fuel years ago but my pressure dropped before it died. I was actually watching fuel pressure mostly on the last drive.

I did another continuity check across all the injector solenoids back to the 42 pin connector and they ranged from 3.2-3.4 ohms.

I am open to ideas if anybody has any more, and again thanks for the replies.
 

dsberman94

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Cam gear could be walking. Any contact marks on the front of the cps?
Idm itself could be bad. Old/wrong oil. Oil aeration from a bad seal on the pick up tube.
Extended cranking without starting will throw a cps code. Clear codes and get it running to see if it comes back.

If it passed a buzz test the injector wiring and injector solenoids are fine. Fuel pressure is good.
 
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501 96 7.3

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I checked for marks on the cps, none there. I have been using LE oil for about 4 intervals. I thought about sending IDM to Swamps to check it, unless there is another way to check it.?

I worked the old girl pretty hard last month. I hauled 143 tons of logs to the mill, 16 loads. Was only about 15 miles from the mill. I hope it isn't the cam gear walking.

I did some reading on Dead Head Diesel last night about a purple cps, I think that is what I had in there from 4 years ago. I may try one more cps.
 

ToMang07

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I have a couple old Ford black ones still.

Sent from my SM-G960U using Tapatalk
 

501 96 7.3

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So some bad news, while working on the truck I let a blue paper rag get sucked through the engine. I did a compression check and #1 cylinder is completely dead. #7 is at 300. 3,5,6,8 are about 350-360 2 and 4 are above 400. I assume the values are stuck open with rag in them on #1? What is next step?

Thanks for the offer on the cps. I will probably take them, shoot me a pm.
 

501 96 7.3

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Ok on #1 cylinder I removed the rockers and pushrods, I assume the valve closest to the front of the motor is the exhaust and the one towards the rear of the engine is the intake. If this is the case the pushrod on the intake is bent pretty good, hopefully causing my compression issue.
 

501 96 7.3

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I finally have an update. Dsberman94 has it right, long story short I sent the idm to Swamps and they said it was bad. So bad it was unrepairable. I do have another idm to try tomorrow.
 

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