CPS trouble or something else?
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CPS trouble or something else?
Howdy! I've got a 2002 F250 7.3 with 220K miles. No real trouble until now. Died on the highway with no previous symptoms. Checked codes and pulled P0340 "Camshaft position sensor a circuit" & P0470 "Exhaust pressure a circuit".
Would not restart. Towed home and replaced the CPS with Borg Warner aftermarket. Also cleaned the exhaust pressure sensor and tube. Started right up but ran rough(misfire and chatter at 1500+ rpm). After about 20 minutes suddenly died again and would not start. Let it rest for a couple hours and started right up with continued rough/chatter. Threw the same CPS code so replaced the new CPS with another BW aftermarket CPS. Same outcome. Went dealer and got OEM CPS. Same outcome. Always restarts after a couple hours with same rough spots at 1500+ and dying after short while.
I can read codes but don't have much other diagnostic equipment.
What do I check next?
Thanks for your help.
Would not restart. Towed home and replaced the CPS with Borg Warner aftermarket. Also cleaned the exhaust pressure sensor and tube. Started right up but ran rough(misfire and chatter at 1500+ rpm). After about 20 minutes suddenly died again and would not start. Let it rest for a couple hours and started right up with continued rough/chatter. Threw the same CPS code so replaced the new CPS with another BW aftermarket CPS. Same outcome. Went dealer and got OEM CPS. Same outcome. Always restarts after a couple hours with same rough spots at 1500+ and dying after short while.
I can read codes but don't have much other diagnostic equipment.
What do I check next?
Thanks for your help.
Hotshot
Joined: Mar 2014
Posts: 10,750
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From: Douglassville, PA
I would check your fuel flow, those symptoms can be created by the common problems with the fuel tank pick up assembly. How much fuel is in the tank? When the problem arises the firs symptom is running out of fuel at 1/4 tank. Search Hutch mod for details.
Elder User
Joined: Sep 2011
Posts: 979
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From: Vancouver
And the other often overlooked problem (other than low oil level) is under the cable harness leaving the 42 pin connector running toward the PCM. A ground fault on wiring in harnesses can cause multiple codes, seemingly unrelated. If you have squirrels, mice etc, look for physical evidence (their leavings). They love to chew on wiring. Also, look at the ground wires just to the left of the PCM (left of the foot pedal for the parking brake behind the plastic cover) to confirm a good clean connection.
Larry
Larry
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From: Oakdale, CA
Also make sure you check the wiring and harness for the CPS itself. These can become damaged as well. If you continue to throw CPS codes, this may be telling you something.
No other codes besides the original two?
No other codes besides the original two?
Laughing Gas
Joined: Jan 2007
Posts: 870
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From: Carbondale, CO
I agree. Check the CPS wiring for any chaffing, look at the connector for bent pins. Monitoring ICP would be helpful. Perhaps "TorquePro" on a phone? Is the tin nut on the IPR sensor?
Cargo Master
Joined: Nov 2005
Posts: 2,768
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From: East Tawas, MI
I'm with Mark,
My advice (never been great) put the original cps back in and get to square one.
Change fuel filter (no mention of that and inspect bowl for sanitary reasons.)
It sounds to me you do indeed have a fuel delivery problem.
How old is your pump and have you ever had your tank down???
Denny
My advice (never been great) put the original cps back in and get to square one.
Change fuel filter (no mention of that and inspect bowl for sanitary reasons.)
It sounds to me you do indeed have a fuel delivery problem.
How old is your pump and have you ever had your tank down???
Denny
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Joined: Dec 2012
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From: Oakdale, CA
I am somewhat surprised it didn't throw a P12xx code related to ICP. However, come to think of it, when my IPR started to have issues it didn't throw any codes either.
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