Hello, have a bit of an issue here. Here is what happened:

2007 1500 Megacab with 5.7L and 200,000 miles.

Towing a half-loaded (6x12) trailer for about 500 miles. Never exceeded 70, occasionally used cruise control on flat areas. No warning that anything was wrong, no CEL. RPM while in straightaways was just under 2000. I never hit the towing button because I figured the load was so light (frankly I forgot).

Got about 300 miles behind me and truck simply dies. Throws code PO335 for crankshaft position sensor A circuit. Pull to the side of the road and truck will not start. Tries to start but will not turn over.

I spend the next 3 hours on the side of the interstate and eventually had a new sensor delivered to me from Autozone by a really friendly Instacart delivery guy.

Able to change out the part in about 15 minutes (have done is before a couple of years ago. Try to start, no change whatsoever. Feeling a little desperate (200 miles from home, 2 dogs and my son in a hot truck) I tried it again and let it try to start for the duration. Lo and behold it started.

I hold my breath and start driving. Same CEL (P0335) comes in immediately after I started it, but my truck is running and I have to get home.


Here is what I notice on the drive (made it home, no stalling):

Truck RPM is higher while driving roughly same speed. I quickly realize the truck is not dropping into overdrive. Just to check I press the cruise control button and the light won’t even turn on. I don’t want to press my luck continuing to push buttons so I leave the tow button alone (still not lit).

I notice that when I lay off the pedal the RPMs drop down to 2000, and when I press the pedal to regain speed the CEL light flashes again. I figure that is another code coming in. Now it was throwing cylinder 5 misfire.

I get home (without turning the engine off during the rest of the drive).



The next day I clear the codes. The engine will start, again after a few agonizing seconds of trying to turn over but the P0335 code is back (and no other codes). I turn in the trailer (now empty).

One other piece of data which drive my troubleshooting. On the wire bundle that passes by the oil filter (which among other wires includes the crankshaft position sensor) the outer plastic sheath has completely cracked and fallen apart for the 6 inches in the vicinity of the filter. Its dirty, but I didn't notice any bare or broken wires, but that of course doesn’t mean much at this point.



So based on the experience of the folks that own these trucks where do you think I should start?



-Should I start off with buying a Mopar sensor and changing out the Autozone one?

-I wasn’t aware of any procedure the last time, but is there a procedure I should do when replacing this kind of sensor to allow it to learn my truck?

-Should I leap into electric troubleshooting at the sensor connection?

-Considering cylinder 5 is on the other side of the engine (and I assume cylinder 5 wiring is not impacted by the plastic sheath issue), was that most likely just a transient condition/code caused by the issues with the crankshaft sensor? It hasn't returned, but on the other hand when I drove to turn in the trailer I never cracked 55 mph.



If anyone has any past experience with similar indications and you figured it out, please let me know. I don’t want to simply throw parts at it and would like to figure out where the issue likely is to save troubleshooting time.

 

Yep. Install a genuine mopar sensor. If you search on the Dodge part number, you can generally find them quite a bit cheaper than dealer pricing.

Install new sensor, clear codes, start engine. Code come back? If not, grab ahold of that wiring harness by the oil filter, and twist it around in any direction you can. (engine running. be careful) See if you can make it die.

 

Sounds like a plan. Will post results, thanks!

 

Alright, finally got the MOPAR part today and put it in snugly. No change. It takes 5 or so seconds to start, will start, but immediately throws the same crankcase position sensor ckt A code.

Is there any way to troubleshoot the electrical with a multimeter? I mean my next line of action seems to be replacing the connection and the wiring up to the spots past around the oil filter where I noticed that the plastic sheathing is cracked and gone. Is there anything else I should do short of that that is easy? (I hate to sound lazy, but I am definitely looking to do what I need to fix the truck vice simply replacing everything I can think of hoping to fix it).

 

Can check continuity on the wires..... set/connect your meter, then manipulate the harness, see if it loses continuity.

Another member had a problem with the connector itself, the metal tubes the pins insert into had expanded, and he was getting good contact....

 

I saw where one pin is 5v (with the key on), another is ground, and the other is the signal coming out of the sensor. That is my next step... Will keep the thread posted, unfortunately I don't have a lot of time to mess with it but it has to get done.

 

If it's only 1 wire with breaking insulation. I would splice in a new wire. That's cheap.

 

Alright, quick update. I disconnected the connection and the knock sensor to pull the wires back around the oil filter. All three wires for the crankcase sensor have bare wire for 1-3 inches around that spot. I jury-rigged it with duct tape (temp fix) and it starts right up, no codes. I have ordered a new connector from RockAuto that comes with what I hope is a sufficient length of wire to allow me to cut back all three past the problem area, and just bought some butt connections to allow me to properly fix it (and some of the plastic sheathing so it won't immediately be dealing with the heat from its location around the filter.)

Feels good to know I found the issue, now I just need to fix it permanently.

 

You should solder those connections, and then heat shrink tubing... butt connectors are notoriously unreliable in hostile environments.

 

Anyone happen to know the gauge wire for this sensor? Is it 18? I cant find anything that states it for my 2007.