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loud91rs
06-28-2013, 09:29 PM
My grand cherokee recently started cranking over a long time before it would start. It was throwing a code p0335 which is the crank position sensor. I replaced it with a sensor from carquest and it is still doing the same exact thing with the same code. I then replaced the cam position sensor just in case because I heard they were tied into the same circuit. Still the same thing, same code. The car is starting hard, and staying in what I believe is limp mode (won't run on 8 cylinders, won't shift to OD, traction control stays off) It's a 2007 Jeep Grand Cherokee 4x4 5.7L Hemi. Any ideas? Think I should try another crank sensor? I tried undoing the connection to the battery to reset the ecm but that did nothing. I checked the codes via a hand reader, as well as using the key and display method. Both times it said the same code. Any ideas? I don't want to take it in. :chair:

Prince Valiant
06-28-2013, 11:28 PM
How long did you leave the battery disconnected? Takes at least 10 minutes before the ECM will reset itself.

Another possibility, though it'll usually show a code for this is low voltage (usually an old/bad battery is the cause). Low voltage will cause all kinds of crazy stuff to happen (trip codes, relays, lights/locks/etc to randomly go off/on).

How are the battery terminals? Again, corroded terminals can cause goofy stuff to occur.

Another possibility is a dirty terminal/wire harness connection elsewhere...when you disconnect the battery, try diconnecting the PCM/ECM and seeing that the connections are clean.

There is a possibility that it's not that the sensors are bad, but are absolutely right...there have been some hemi's that have had excessive wear of the cam sprockets/gear go bad, leaving the cam/crank timing "off" from each other...though I'm not familiar with the symptoms these cases would result in.

Irish
06-29-2013, 06:58 AM
Has the fuel filter ever been changed?

loud91rs
06-29-2013, 07:51 AM
Fuel filter has never been changed. Think that would be a cause of my code?

Battery terminals are super clean. I will have the battery tested. I really hope it's not the sprockets/gear.

Prince Valiant
06-29-2013, 09:13 AM
Also look at the connection itself to the crank position sensor...if their is any corrosion/dirt/etc or broken wires there....

-stew-
06-29-2013, 10:48 AM
Leaking fuel pressure regulator (if it has a vacuum regulator) or possibly a leaking injector? Sounds like maybe it's loosing fuel pressure and it takes a bit of cranking to get the fuel pressure back where it needs to be and the extended cranking could cause the crank sensor code to trip. I think it should run on all eight in limp in mode. It may not be running on all eight, but don't assume the ECM is making it run that way.

Irish
06-29-2013, 10:49 AM
Fuel filter has never been changed. Think that would be a cause of my code?

Battery terminals are super clean. I will have the battery tested. I really hope it's not the sprockets/gear.

I am not sure what could be causing your code, your symptoms sound similar to what I experienced with my GCL. No codes were thrown, however the fuel pressure was very low.

Check your fuel pressure at the rail.

loud91rs
06-29-2013, 11:55 AM
Found the issue. It took some digging but one of the wires was broken. I am back up and running. Thanks guys!

Prince Valiant
06-29-2013, 07:13 PM
Where was the wire broken at? Near a source of heat? Over a sharp bend? Near the connection?

spooln30
06-29-2013, 11:23 PM
I see you fixed it but for future reference an easy way to see if the crank/cam sensors are working. Hook up a scan tool that has viewable data and see if you have a rpm reading on the scan tool.