Jeep Wrangler TJ Crankshaft Position Sensor Replacement

I need help with 2006 Lj, 120K miles. I do most of my own repairs(spark plugs, new catalytic converters and cat sensors, all within last 6 months) only other engine related component replaced was the speed o gear after putting 33" tires on a year ago.
Yesterday (10/23/2018) started fine and drove for about 25 miles with no issue, filled up with gas and on to work. Then after work, jeep will not start - Turns over and sounds good(no odd sounds) but will not fire. No codes thrown, I have poured through forums with nothing definitive except Crank Position sensor, cam position sensor or bad wiring between either and the ECM. Another person had an issue with timing chain being stretched just enough to throw the timing off after running a while and causing the crank and cam position sensors to not be in sink. Also on every forum they don't use the same terminology for the crank position sensor and camshaft position sensor...Some use CKP crank and some use CPS for camshaft while others use CPS for crank.
Many auto parts store sell crankshaft sensors that look like the camshaft sensor...
Anyway, i need to get my jeep up and runnings, its my only vehicle at the moment. While i am not oppose to changing both sensors, but i'd like to find the actual issue and not easter egg.
 
I'd like to say, thanks for all the help but as you all can see, no replies. I thought I'd up date this anyway. So I, as I was saying, engine turns over but no fire...got a code reader on it and it did come up with Crank shaft and cam shaft out of sync but never tripped the CEL. Replaced both sensors still no joy. Started tracing the wiring harness, all looked good. Read on another post that could be a fuel delivery issue so I started down that rabbit hole and it proved to be a bad fuel pump. Now I guess it could just be really bad luck that all three went bad at same time, I do have 118K miles so i'm sure they all were due for replacing. Even more bad luck, after installing new fuel pump and getting my Lj running again, I blew a transmission line just before it goes into the cooler at the bottom of the radiator. Easy fix in the parking lot of the local Napa auto parts but it scared the hell out me cause i thought I was on fire with all the smoke, having just put in a new fuel pump. Grand total of 345 dollars and a few bloody knuckles I am back on the road.
 
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James Brewer said:
I'd like to say, thanks for all the help but as you all can see, no replies. I thought I'd up date this anyway. So I, as I was saying, engine turns over but no fire...got a code reader on it and it did come up with Crank shaft and cam shaft out of sync but never tripped the CEL. Replaced both sensors still no joy. Started tracing the wiring harness, all looked good. Read on another post that could be a fuel delivery issue so I started down that rabbit hole and it proved to be a bad fuel pump. Now I guess it could just be really bad luck that all three went bad at same time, I do have 118K miles so i'm sure they all were due for replacing. Even more bad luck, after installing new fuel pump and getting my Lj running again, I blew a transmission line just before it goes into the cooler at the bottom of the radiator. Easy fix in the parking lot of the local Napa auto parts but it scared the hell out me cause i thought I was on fire with all the smoke, having just put in a new fuel pump. Grand total of 345 dollars and a few bloody knuckles I am back on the road.
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Glad to hear that, and thanks for the update!

In the future, you may want to post a new thread instead of adding onto an existing one. I only say that because it will get much more attention this way. I missed your posts because they were a part of this existing thread, that's why.

I'd say that is very bad luck that all three went bad at the same time. However, like you said, at 118k miles and well over 10 years of age, it's due for maintenance anyways.
 
Irving said:
I had a similar issue regarding code P0320, my 98 auto TJ run rough on idle or gear reving up by itself, and usually the condition went away after some driving... so before I spend 100+ bucks on a new crankshaft position sensor I plugged it off and removed it to check its condition (I was going to diagnose it but I tried manually adjusting first), I gave it a clean with a rag checking the condition of the wires and connectors and since nothing looked damaged I installed it back on... when I tried to tighten the screw back on I noticed that the screw was really short and could not hold tightly the CPS, so I replaced the screw... first I just let the CPS go in all the way and tighten the screw... when I turned the engine the reving up was still there, then I tried placing the CPS all the way out from the hole as possible and tighten the screw again (the CPS hole has a slot) and VOILA! the condition was no longer there... but the code and check engine light where still on... I drove around for a while with the light still on but no reving condition... the next day I started the jeep and the check engine light was gone!!!

PS. The screw I had on and had replaced was M10 not a 7/16...

I think I got lucky but you never know if you don't try!
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The new MOPAR CPS has a cardboard spacer stuck to it to set the gap. Once the engine starts, the cardboard tears off. That is probably why moving the CPS out in the slot worked. I have the same problem with the screw being too short. Off to the hardware store to get a longer one. Looks like 10mm head with M7x1.0 threads.
 
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Hi All.
I have jeep TJ 4.0 2002 with Automatic transmission. I had a problem from yesterday. My jeep is not starting up. As i on the switch panal lights arw on but none of the gauges are responding. And a yellow light with cross on key is on. Its also giving "no bus" code in odometer with chk engine light after some time you left switch on.
I have cleaned the panel contact. Than from the forum somebody suggested in previous discussions about testing CPS. That's if you remove CPS grip and gauges start working so its time to replace CPS.
Just want an expert recommendation as i am in Pakistan and its difficult to get parts of Jeep here so i want to confirm so that i can import any way.
Regards

20190726_103105.jpg
 
Just to confirm that depending on your model year, engine model, and transmission type, that the crankshaft position sensor can be found on either side of the engine and many combinations have a different p/n depending on whether the automatic is an automatic or manual. I had to change my CPS to the automatic style after converting from a manual to automatic transmission. One has one mounting bolt hole and the other has two mounting bolt holes. On my '97 4.0 the CPS was high up on the driver's side but on later model years it is on the passenger side. So do your due diligence and don't take someone's word on the CPS p/n as it's probably not correct for your particular Jeep.
 
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I've had my 05 Wrangler for about 8 years now. It was willed to me from my grandfather. Through the years I've had to do some minor and major fixes to it. About to change the CPS. Just wanted to thank everyone on the site. I don't have family or friends that know anything about Jeep's and being in a small town the shop want you to pay with your soul to work on anything. so I've done all this on my own with the help of you guys. This is my first post on here. Just wanted to throw out some praise to all of y'all. Thank you.
 
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Put the jeep away last night running perfect. This morning it cranked and cranked but never fired up. Did a little research while at work and determined a CPS replacement was likely needed (just crossed over 170,000mi).

I picked up a $30 sensor from Advance and it came back to life. I didn't have the time to source a Mopar part, but will be getting one soon to keep on hand for when this one fails.

The install is dead easy, hardest part is getting the electrical connector apart. One thing to note that I found on another post is to confirm you are not installing into a "gap" by sticking your finger in the hole and making sure you hit metal. If you install in a gap it will not be spaced correctly.
 
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Just swapped out mine today. Seems just like @Jerry Bransford said location and part number varies depends on model year. Details for mine is as below.

2004 TJ Unlimited Auto Transmission
Part number 4727451AA

Passenger side of the bell housing just behind the Starter motor.
 
I got a P0016 code on my Wrangler. Don't have any issues with rough idle and it has been running fine. I had initially got a CEL with P0016, but the CEL went off on its own. However, I still have the P0016 code. I am guessing there is bad wiring to the Crankshaft Position Sensor. Any ideas where the sensor is located on 06 Wrangler. I see a sensor at the top of Bell housing but that is attached to the bell housing and has the inverted Torx E12 bolt. Is this it? or am I am missing anything here? Please help
 
OFFRD TJ said:
I got a P0016 code on my Wrangler. Don't have any issues with rough idle and it has been running fine. I had initially got a CEL with P0016, but the CEL went off on its own. However, I still have the P0016 code. I am guessing there is bad wiring to the Crankshaft Position Sensor. Any ideas where the sensor is located on 06 Wrangler. I see a sensor at the top of Bell housing but that is attached to the bell housing and has the inverted Torx E12 bolt. Is this it? or am I am missing anything here? Please help
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Auto or manual? On my manual it was on top of the passenger side of the bell housing, but it was a hex head. I’d assume it’s similar on the auto but don’t know enough to say it’s 100% the same. Of course POs do weird stuff all the time, that would be a very odd one to change out.
 
rasband said:
Auto or manual? On my manual it was on top of the passenger side of the bell housing, but it was a hex head. I’d assume it’s similar on the auto but don’t know enough to say it’s 100% the same. Of course POs do weird stuff all the time, that would be a very odd one to change out.
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Manual. I think I found it. On 05-06 model years they are on the passenger side with a 10mm bolt. I saw someone posted a video on youtube for their 05 wrangler. Does the manual have a different sensor than automatic ones? I found the Mopar part #

Crankshaft Sensor - Mopar (4727451AA), but for some reason, it said "After 02/24/03. Automatic Transmission." in the description. Any ideas?​

 
OFFRD TJ said:
Manual. I think I found it. On 05-06 model years they are on the passenger side with a 10mm bolt. I saw someone posted a video on youtube for their 05 wrangler. Does the manual have a different sensor than automatic ones? I found the Mopar part #

Crankshaft Sensor - Mopar (4727451AA), but for some reason, it said "After 02/24/03. Automatic Transmission." in the description. Any ideas?​

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That’s the one I have in my manual
 
Chris said:
There are several reason why you would need to replace your Jeep TJ Wrangler's Crankshaft Position Sensor (or CPS for short) with the most obvious one being that your 'check engine' light has illuminated and a quick check with an OBDII reader indicates you have thrown one of the following MIL codes.

P0219 - CPS Overspeed Signal
P0320 - No Crank Reference Signal at PCM
P0387 - CPS Voltage Supply too Low
P0388 - CPS Voltage Supply too High

For me, my Jeep wasn't throwing any codes and so I wasn't completely sure that this was something I needed to replace. What lead me to think that it may need to go was the fact that I now have over 120,000 miles on the odometer, I have already replaced my O2 sensors and still had various engine issues including a rough idle under specific conditions. Specifically, my engine would run very rough on cold mornings or after driving it a long time with the AC on, turning off the engine briefly and then starting it back up again. I had also experienced times when climbing up long highway hills the engine would run quite rough... almost as if it were misfiring. Now, I should tell you that things are better since installing a new CPS but my engine is still running far from perfect.

Anyway, this write-up should help you out if replacing your Crankshaft Position Sensor is something that you need to do.


What You Will Need
  • Crankshaft Position Sensor (Part # 4897321AA)
    (Be sure to purchase the OE Mopar sensor in the above link. Aftermarket sensors are widely known to cause issues with our TJs.)
  • 7/16" Wrench & Socket
  • Ratchet
  • Inch Lb. Torque Wrench
  • 3" Drive Extension
  • Small Flathead Screwdriver

Instructions
Your Jeep TJ Wrangler's CPS is located on top of your transmission's bell housing as can be seen in this photo which was taken standing on the driver side of my Jeep and looking down into the engine compartment.

View attachment 12292

The bolt or bolts (different years have the CPS secured to the bell housing in various configurations) can be access either from the engine compartment or from underneath your Jeep as shown in this photo. Using a 7/16" wrench or socket with 3" drive extension, remove the bolts securing the CPS in place and pull it out of the bell housing.

View attachment 12289

The wiring harness for your Jeep's CPS wraps around the engine block and it's plug can be found on the passenger side it, behind the oil filter and next to the fire wall as shown it this photo.

View attachment 12291

The CPS wiring harness plug may be a bit difficult to unplug and if needed, a small flat head screwdriver can help. Just be careful not to use too much force as you will break the plastic plug. Once unplugged, remove the CPS out of your engine compartment.

View attachment 12290

Insert the new CPS into your Jeep's bell housing and secure it in place to 60in. lbs. of torque using the factory bolt(s) and a 7/16" wrench. Then, pass the wiring harness around the back of the engine block so that the plug is on the passenger side of your Jeep.

View attachment 12293

Plug in your new CPS wiring harness making sure that it clicks into place.
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When removing the old CPS, I noticed the felt spacer was missing, with just a tiny piece of it still stuck to the sensor. I was able to put my finger into the hole and feel the old felt down in there, but am unable to get it out and in doing so, it fell to a position that I an no longer feel it. I tried to get a vacuum hose in there to suck it out, but with no success.

Will it just fall down into the oil pan where I can remove it from there? Not sure what it looks like in there or if I can get it out without taking the whole thing apart.
 
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