Jeep Garage  - Jeep Forum

Jeep Garage - Jeep Forum (
-   Tech Tips/DIY/How to (
-   -   How To: Replace Crankshaft Position Sensor (

JeepMe 12-12-2012 07:58 PM

How To: Replace Crankshaft Position Sensor
This is going to be a how to on replacing the crankshaft position sensor on the 4.0L motor in the Grand Cherokee. This is by no means the ONLY way or "correct" way to replace the sensor. This is only the way I changed the sensor. I also never had to get under the Jeep to accomplish the task.

Tools Needed:
* ratchet
* universal joint
* socket extension
* 10mm socket
* 11mm socket
* 10mm wrench
* needle nose pliers
* string
* flathead screwdriver

I had to replace mine due to the Jeep not starting and throwing the P0320 code. Onto the good stuff (yes, the pictures were staged for this guide).....

* The first thing is to remove the air box so it's out of the way. This will make it easier to remove the sensor later. To remove the air box you need to first remove the 1 bolt holding it in place using a 10mm socket (see location below).

Then remove pull on the valve cover breather tube (see below, red circle on left). Wiggle it some while pulling and it comes right off. Next, loosen the pipe clamp that holds the box to the tube from the air filter (see below, red circle on right). Wiggle the tube while pulling away from the air box and it comes off easily.

Next you need to loosen the pipe clamp that holds the air box down onto the throttle body (see location below). Once that's loose, wiggle the box while pulling up and it will pop free from the throttle box. Place the box aside for later.

* Now I removed the bottom part of the dash. To do this I started by removing the plastic piece right below the gauges (see picture below, the piece my hand is on). This is easy to remove, just pull up and out on it and the clips release. Set piece aside.

Next I removed the very bottom plastic piece from the dash. It's held in place by two 10mm bolts on the bottom, 3 Phillips screws on the top and side, and 1 clip on the left half. The below pictures show the location of the 3 screws and 2 bolts (starting on left side and moving in a clockwise direction). Once the bolts/screws are removed, pull on the plastic and it comes out.

* Next is to remove the air vent that blows air on your feet. It's located just to the right of the plastic panel you just removed earlier (see below).

It's only held in place by one Philips screw that's hidden behind the vent (see pictures below, arrow points to location where screw was). Use a short screw driver to remove it. Then pull the vent out.

* Next it to remove the plate on the firewall that the shifter cable runs through. It's held in place by two 10mm nuts (see picture below, one nut is hidden just out of view). Remove those by using a 10mm socket on the bottom one and a 10mm wrench on the top one. Then use a screwdriver to gently pry the cover up over the studs. To get the plastic out of the way, pull it over the studs and then slide it down the cable out of the way.

If you look through that hole in the firewall, you'll see the crank position sensor and the one 11mm bolt that holds it in place. I forgot to take a picture before I removed the sensor, but this is what you should see. The red arrow shows where the 11mm bolt would be located. The yellow arrow shows the hole where sensor sticks into the bell housing.

* Now you need to remove the actual sensor. You'll notice from the picture above, the 11mm bolt isn't exactly centered on that hole. To get to it I used a 11mm socket, universal joint, and an extension (in that order). Plug that assembly through the hole, get it seated on the bolt, and take the bolt out. If you're lucky, the bolt will stay in the socket (if you think ahead, get a small magnet and put it in the socket to hold the bolt). If you're like me, the bolt will drop and fall on the ground.

Now that the bolt is out, all you have to do is pull the sensor out of the hold. This is where the fun happens. I got it out of the hole from where the air box was located, use the following two pictures for reference. The first picture is a zoomed out view for location reference (next picture zoom was in the location where I'm pointing). The second picture is zoomed in and the left arrow is where the bolt threads and the right arrow is the actual sensor.

So I reached down to that location and pulled up on the sensor. It popped right out of the hole. Then I gently pushed it back towards the hole in the firewall. Next I went back into the Jeep and took a pair of needle nose pliers to grab the sensor and pull the tab through the hole in the firewall. I didn't have any string, so I attached dental floss (see below).

Now I went to the passenger side of the engine and located the plug. The two pictures below show where the plug should be located (sorry, picture taken after I accidentally ripped the plug away from the wiring). This is set up like the two pictures above. The first is zoomed out and I'm pointing towards where the second one is taken. The second picture shows the location where the plug was attached.

Once you've located the plug (sorry for the bad pictures here), disconnect it by pushing the tab down and pulling. You'll notice that the sensor plug is attached to the wire loom because the plastic is taped to the loom. I pulled on it and it came free (I zip tied it back on later). Now pull on the wires gently and the sensor should come out with the string attached.

* Finally, you'll put the new sensor back in place. Cut the string off the old sensor and tie it to the new sensor. Plug the one end back into the wire loom. Then reach down and roughly route the sensor back the way it came. Make sure that the plug end is extended towards the back of the engine or the sensor won't reach the hole. Now go back inside the Jeep and gently pull on the string. You'll pull the new sensor back to the hole in the firewall. Remove the string and use needle nose pliers to push it towards the hole. Now simply reverse the process above and it'll be set.

The whole thing sounds easier than it really is. It's very aggravating and frustrating. But with some patience, it will all go together.

violant00 06-02-2013 12:04 AM

Re: How To: Replace Crankshaft Position Sensor
Hey man i got to say this was a GENIUS write up for this... ive been trying to figure out for the past 2 weeks how to do this without dropping the tran. Did it today all by myself and it took me only a couple of hours. The JEEP runs amazing now :)

timberlin 07-05-2013 09:30 AM

Re: How To: Replace Crankshaft Position Sensor
I just performed this procedure on my 2001 JGC. It took me a total of 2.5 hours and was tricky at times but it solved my problem. My jeep is running fine now. The pictures and instructions were awesome and totally accurate. I took your advice and put a small magnet in the socket when removing and inserting the bolt for the sensor. It worked and I didn't drop the bolt. The only frustrating problem I had was that I also used dental floss for the string to pull the sensor back into place. The string got snagged on something and I had to really work the cable to get it into a position so I could grab it with the pliers.

One other note. No codes showed up indicating this sensor was the problem. The car would crank and crank but would not start. I came to the conclusion that this sensor needed to be replaced after eliminating any fuel issues. Luckily, after replacing this sensor, the car now starts and runs fine.

Thanks a lot for the post.:)

disruptit 07-14-2013 10:29 AM

Re: How To: Replace Crankshaft Position Sensor
Hi, I have the exact same type jeep. And my error codes said Crankshaft position sensor. So, I'm to the point of actually unscrewing the bolt in the firewall hole.

Question: the CPS on autozone, says it requires another paper spacer that isn't available. What brand did you use. As you didn't mention needing a paper spacer. Or is that actually necessary. Thanks.

timberlin 07-14-2013 11:46 AM

Re: How To: Replace Crankshaft Position Sensor
The sensor brand was BWD and the part number was CSS819 which I bought at Advanced Auto Parts. The part did have a paper-like material at the end of the sensor which I had read about in other blogs.

According to the info sheet that came with the part it says "Do Not remove the paper spacer. It is about .030 inch thick pasted on the tip of the sensor and provides the necessary air gap between the sensor and the engine moving parts. After the engine starts it gets sheared off. If for some reason a sensor is pulled out and has to be reinstalled, a similar spacer should be glued to the sensor tip."

Good Luck.

disruptit 07-15-2013 04:14 PM

Re: How To: Replace Crankshaft Position Sensor
Fixed it, thanks, for the thread, I wouldn't have had a chance without it, and would have had to pay for tow, and someone else to fix.

It's running smooth now, and also, it took two tries before to get it to start, now it starts first try easy. So, it's been failing for 6 months probably.

Thanks Again.

GREGNAPLES 12-29-2013 08:58 AM

Re: How To: Replace Crankshaft Position Sensor
The article was terrific. I would not have been able to do the job without it. A 10mm racheting wrench was crucial for those hidden bolts. Thanks again. Greg.

dlundblad 04-24-2014 08:00 AM

Re: How To: Replace Crankshaft Position Sensor
Long time lurker here. Thank you for the write up. I'll have to give it a try.

DrSayre 06-23-2014 12:35 PM

Re: How To: Replace Crankshaft Position Sensor
Thanks OP for this. It really helped!

All times are GMT -5. The time now is 01:20 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community