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James
James, Ford Technician
Category: Ford
Satisfied Customers: 3588
Experience:  Ford Senior Master Tech, Ford gas and diesel expert, ASE Certified
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Need help with 2004 F350 6.0 diesel. Intermittent starting.

Customer Question

Need help with 2004 F350 6.0 diesel. Intermittent starting. I'm not doing detailed diagnostics right now, just a few general questions regarding ckp, cmp and pcm
Submitted: 1 month ago.
Category: Ford
Expert:  david craig replied 1 month ago.

Hi Im David, do you have any fault codes?

Customer: replied 1 month ago.
no codes. my question is related to what does what. if I had an issue with the wiring for the CKP - could the truck run? What specifically does the CKP do? Once I get it cranked I have no issues.
Expert:  david craig replied 1 month ago.

A crank sensor is used to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control the fuel injection or the ignition system

Expert:  david craig replied 1 month ago.

if you had an issue with the wiring the sensor would not let it start

Customer: replied 1 month ago.
ok so that sounds to me like if the wiring were bad / cracked / pinched then the truck would not run period.
Expert:  david craig replied 1 month ago.

correct

Customer: replied 1 month ago.
2 other questions, is it normal for the cmp / ckp sync to bounce between 0 and 1 while it is running? And I do not have FICM sync until the truck actually starts - is that normal?
Expert:  david craig replied 1 month ago.

its not ideal, but its not unusual. as long as it doesnt vary any more than that, but then again you would have a fault code for those 2 sensors being out of synch

Customer: replied 1 month ago.
ok I know you need more specific details to help further but I won't be able to hook up AE and get readings until tomorrow. could I get back with you to continue or do I need to start another session? I assume need to look at fuel, high pressure oil pump, ipr, etc..
Expert:  david craig replied 1 month ago.

tomorrows cool. ill be here. ill keep this open

Customer: replied 1 month ago.
thanks
Expert:  david craig replied 1 month ago.

you bet

Customer: replied 1 month ago.
I have AE connected if you are around to assist
Expert:  James replied 1 month ago.

I can certainly assist you if a phone call will be easier.

Customer: replied 30 days ago.
hello - do I call someone or do they all me?
Expert:  James replied 30 days ago.

I am trying to send you a phone offer but it won't allow me to. If you are still able to send me a phone offer I can accept it right away and give you a phone call.

Customer: replied 30 days ago.
It won't let me either since I had already accepted before.
Expert:  James replied 30 days ago.

On your side does it say someone else accepted your phone offer by chance?

Customer: replied 30 days ago.
it has David Craig first, and then James
Expert:  James replied 30 days ago.

Hmm I will email a moderator and see why I can't send you an offer. Unless I am able to help you on here? It is up to you.

Customer: replied 30 days ago.
lets do this now since we are both on. I have AE hooked up. FICM no sync and CKP / CMP no sync. battery voltage is down to 11.9 because I was trying to start it. I've got a charger back on now. FICM main power 47.5
Expert:  James replied 30 days ago.

Before you can have FICM sync you need to have regular sync.

Expert:  James replied 30 days ago.

If you aren't getting regular sync I would remove the camshaft sensor and clean the mounting surface all around it and see if this helps.

Customer: replied 30 days ago.
yep did that - removed camshaft sensor, cleaned. no change. it will eventually crank and runs almost perfect. thats what I can't figure out. tried wire jiggle - although new wiring harness installed 3 months ago. how about the pcm, is there a way to test it?
Expert:  James replied 30 days ago.

The only way to test the PCM is with an oscilloscope. Have you replaced the cam sensor or crank sensor yet?

Customer: replied 30 days ago.
i have not replaced them no. again, if there were a problem with either it would never start yes?
Expert:  James replied 30 days ago.

not true. I would begin by replacing the cam sensor. The cam sensor is know to only cause a no start sometimes. It just depends on how the sensor fails. The camshaft sensor has failed many different ways though.

Customer: replied 30 days ago.
ok i'll give it a try
Expert:  James replied 30 days ago.

sounds good. Let me know how it goes.

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