**Long crank time and no overdrive when cold** Works when warmed up and restarted
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Joined: Jul 2012
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**Long crank time and no overdrive when cold** Works when warmed up and restarted
For about a year I've had this nagging code come up (P0335 Crank Position Circuit) and a host of irritating symptoms, and I have exercised almost every trouble shooting tactic in the Ram Service manual as well as my own experience as a mechanic and many hours of forum & google searches, so I figure I will explain my issue best here:
Last year I rebuilt the top end of my 04 5.7 Hemi Ram engine after one of the 3 year old Engine Tech brand lifters failed and took out the cam, I replaced the camshaft with a 04 5.7 Hemi Durango Cam, Melling Lifters, new timing chain and tensioner set, installed new valves and lapped the seats. I remember the engine running great, getting awesome fuel mileage and massive power for the first few weeks after rebuild and then I had a problem out of the blue show up as:
Symptom #1: a long crank time: 5 seconds of cranking then engine starts
Symptom #2 Half power engine (goes to 3500 rpm stalls out) until warmed up 10 minutes and restarted, then full power resumes (restarts instantly when warmed up)
Symptom #3 Transmission omits overdrive until restarted when warmed up....Happens along with the long crank time and half power. When engine is warmed up completely after 10-15 minutes I can restart the truck and have full power and all of my gears and everything works normal.
Symptom #4 Random choke offs.
Truck will always restart instantly when warmed up and have all of its gears and all of its power and run great, but as soon as it cools off, the long crank time and omitted overdrive are back in full force annoying me.
What I've done:
Followed the Ram Service manual diagnostics from step 1-14
Checked for bad grounds/shorts can't find anything, even ran a new ground and power wire to the sensor to eliminate that as a possibility (put back to normal now). K900 Ground is shared with several other sensors that work normal as with the power feed.
Checked ohm readings- within spec
New Crank and Cam sensors
Checked the entire harness for damage- nothing
Tried my brand new backup PCM that was programmed to vin
I've been studying several schematics for months and I'm just at a loss, I find it weird that the cam sensor symptom & code is followed by the transmission losing overdrive and that they both occur when the engine is not up to operating temperature and they both go away once operating temp is well establish and truck is restarted.
Now one thing I've suspected but I can't find clear proof of it in the schematic is that my trans shift solenoid pack intermittently has issues where it'll stick me in 3rd gear until I restart, I have to get that replaced for sure but I wanted to get the engine running good before I blew my cash in the wrong places. Now when looking at the engine and trans harness, I do notice that the crank sensor does feed into the transmission harness, whether its integrated in some fashion with that circuit I have no clue.
Any help would be appreciated!.
Last year I rebuilt the top end of my 04 5.7 Hemi Ram engine after one of the 3 year old Engine Tech brand lifters failed and took out the cam, I replaced the camshaft with a 04 5.7 Hemi Durango Cam, Melling Lifters, new timing chain and tensioner set, installed new valves and lapped the seats. I remember the engine running great, getting awesome fuel mileage and massive power for the first few weeks after rebuild and then I had a problem out of the blue show up as:
Symptom #1: a long crank time: 5 seconds of cranking then engine starts
Symptom #2 Half power engine (goes to 3500 rpm stalls out) until warmed up 10 minutes and restarted, then full power resumes (restarts instantly when warmed up)
Symptom #3 Transmission omits overdrive until restarted when warmed up....Happens along with the long crank time and half power. When engine is warmed up completely after 10-15 minutes I can restart the truck and have full power and all of my gears and everything works normal.
Symptom #4 Random choke offs.
Truck will always restart instantly when warmed up and have all of its gears and all of its power and run great, but as soon as it cools off, the long crank time and omitted overdrive are back in full force annoying me.
What I've done:
Followed the Ram Service manual diagnostics from step 1-14
Checked for bad grounds/shorts can't find anything, even ran a new ground and power wire to the sensor to eliminate that as a possibility (put back to normal now). K900 Ground is shared with several other sensors that work normal as with the power feed.
Checked ohm readings- within spec
New Crank and Cam sensors
Checked the entire harness for damage- nothing
Tried my brand new backup PCM that was programmed to vin
I've been studying several schematics for months and I'm just at a loss, I find it weird that the cam sensor symptom & code is followed by the transmission losing overdrive and that they both occur when the engine is not up to operating temperature and they both go away once operating temp is well establish and truck is restarted.
Now one thing I've suspected but I can't find clear proof of it in the schematic is that my trans shift solenoid pack intermittently has issues where it'll stick me in 3rd gear until I restart, I have to get that replaced for sure but I wanted to get the engine running good before I blew my cash in the wrong places. Now when looking at the engine and trans harness, I do notice that the crank sensor does feed into the transmission harness, whether its integrated in some fashion with that circuit I have no clue.
Any help would be appreciated!.
Last edited by JoshSlash87; Oct 8, 2020 at 06:59 AM.
Amateur
Joined: Sep 2020
Posts: 27
Likes: 2
How does the live data on the CPS look? How does the live RPM data look when you're driving around? If the transmission is looking at that sensor to understand the RPM of the engine, you could definitely end up in a limp mode without that data.
The questions to answer:
1. Is the data there, then just 100% dropping out
*or*
2. Is the data there, then getting wonky.
A dropout would have me looking at consistency of not only the ground, but also the 5V power. Your observation that there is a feed to the transmission is important, as a fault in the transmission control module could drag down the feed from the CPS as well.
Wonky data would have me back probing the sensor itself with a scope to see if the data is OK there vs. what the ECM sees. If what's coming out of the sensor is garbled, then I would ask where you got the sensor and who the manufacturer is.
The questions to answer:
1. Is the data there, then just 100% dropping out
*or*
2. Is the data there, then getting wonky.
A dropout would have me looking at consistency of not only the ground, but also the 5V power. Your observation that there is a feed to the transmission is important, as a fault in the transmission control module could drag down the feed from the CPS as well.
Wonky data would have me back probing the sensor itself with a scope to see if the data is OK there vs. what the ECM sees. If what's coming out of the sensor is garbled, then I would ask where you got the sensor and who the manufacturer is.
