I recently went through the whole T/C lockup problem and found it to be a bad ground. I fixed the issue and no problems until today. It started going in and out of lockup in 3rd and 4th but not like it was doing before. Before it was at steady throttle now it does it at different throttle positions. Also I just got a P0336 code. My question is will a Crankshaft Position Sensor cause T/C lockup issues or am I getting the code because of T/C lockup problem?

Just do the diagnostic the best you can. But when a error code is thorwn 9 times out of 10 the code it throw for its device.

 

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/59-obdii-error-codes/175-p0336-crankshaft-position-sensor-signal

Thanks Mike.

I have the same code poping up and a couple times the tach has dropped to 0 for a few seconds or so.

I looked at the diagnostics and am seeing that the issue is generally a fault in the wires to the ecm, the sensor, or the ECM.

Is this correct? If all tests turn out fine I should replace the sensor correct?

You're right on. Mine turned out to be the sensor itself. Check you're connections, harness, wires etc. If you need a sensor I would suggest getting an OEM one. The crank sensor on my truck had been replaced with an aftermarket one shortly before I bought it.

Thank you 

rlane547

When you say OEM you mean buy a bosch, or just an OE from NAPA?

Edited July 31, 201410 yr by eddielee

No. I mean get it from Cummins or Dodge. You don't want to take a chance because if this sensor fails you are dead in the water. It will crank all day but no start. Cummins technically calls it a speed sensor which is what it is. Just like a wheel speed sensor. So if you ask for a crank sensor and they say speed sensor you are on the right track.

I've had that P0336 with the same issues (sometimes no start, tach drops to 0 while driving, etc.)  I went for about a month or two of that before I finally took the starter off and changed the sensor out with one from Autozone, did that about 4~5 months ago and it ran fine.  Just last week I had the same code trip again while driving and the RPMs went to 0 for about 2 seconds then back to normal (just like before)...  I'm not saying the Autozone sensor is the problem, I'm actually hoping it's a connector/connection problem at this point.  Either way I have to start checking cables and connectors and see what else (if anything) it could be. 

I just got the sensor that I ordered from Genos and I will put it in soon.

As I suspected it is a genuine Cummins part for far less money!

Next to put it on!

Well, I found the problem with the code being thrown this time, but I still don't know what caused the sensor to do what it did (this time).  I finally got under the truck today to put on the new crank sensor (from RockAuto, PC292, super cheap there too) and I found something a little strange.  Once I removed the starter and went to pull the connector off of the sensor, I saw that the little bracket (or brace) that holds or pinches the sensor was not actually holding the sensor like it was when I put it on.  The bolt was super tight as it took a bit of force to take it off so it wasn't a loose screw at the sensor.  I could turn the sensor in the bracket while it was still screwed down in the block...  Normally there is a little wiggle that is there when it's not in the block, the bracket just pinches the sides of it, but when it's in the block and the bracket has that screw in it, it doesn't (or shouldn't) move.  I took it off and the sensor looked OK but I replaced it to be safe.  The bottom part of the bracket I took off was bent way down, the top looked OK, if it was bent it was minimal and I couldn't really tell but the bottom was for sure.  Also on the sensor there was a grove in the part where the bracket pinches it, looks like it turned hard to get that to bend the little metal (or aluminum) bracket if that's what happened.  It looks like the sensor turning (not tilting or being popped back) caused the bracket to do this.  Maybe the screw that holds the bracket to the block might have magically turned counter clockwise and then back enough to space out the little grab arms of the bracket (just kidding)..  Any thoughts on this??  It looks like the sensor either turned hard enough to cause the bracket to open up and let the sensor spin around some, or the bracket just bent down and allowed the sensor to turn.  I'll be checking the sensor bracket for a while now anyway.