Old sensor vs new.

Untie the 550 cord from the old sensor and tie it on the end of the new one. Don't ask what in the world was going on with my weird knots. I doubt I could recreate them if I tried. I will comment, a good slip knot that won't pull off is handy for removal later. Once the 550 cord is secure, plug in the new sensor to the wiring harness.

Back on the inside of the vehicle, gently pull the 550 cord to fish the new sensor back to the access hole. In the following picture, you'll see where it needs to slip in.

We found slipping in the sensor and tightening the bolt in place is difficult because you block your view with your hand/tools. If you have a second person under the vehicle, they can help 'guide' you to the finish line.

As a hint, I slightly taped the bolt/shield to my socket so I could get it started without dropping it.

With the bolt snugged down with the shield protecting the wires, remove the string, attach the push clip for the sensor plug to the side of the engine, reattach the battery, and start it up to verify everything works. Assuming so, reassemble the interior and kick back with a grin for successfully completing an annoying job!

:cheers2:

 

Bloody Hell Chris... the wife must have turfed you out to the garage for all this Lols! :laugh:

Great write up.. hope you sleep well tonight :laugh: :thumbsup:

 

Haha! The project wasn't too bad and only took a couple hours including chit chatting with my brother. The problem was, I had so many visitors stop by, I ended up being out there until 1:00AM!

 

Thanks Chris, will add this thread to my favorites.

 

:thumbsup:

 

it is much easier doing it under the jeep! ive done it twice on our old zj in under 10 minutes each! i used about 3' of extensions, and was able to unbolt it. went into the engine bay, and pulled the old sensor out, and put the new one in. then crawled back under the jeep, and reinstalled the bolt.

im a big guy too 6' 280, and i was still able to do it the "easy" way.

 

that's how i did mine on my WJ. it was much better than unbolting mounts.

 

I couldn't see a way to do it from under. I've heard it is possible and perhaps it is. It just seems entirely too tight to get to the sensor and successfully replace it. Doing it from under looks like an awesome way to drop the bolt and throw wrenches.

I'd love to see pics of that method though as that's definitely the preferred way!

 

This is definitely one of those "what was Chrysler thinking?!" threads. Good write-up.

 

Excellent writeup bro..

 

Thanks! I hoped it would help someone out on here!

 

"Your Mission Mr Phellps ...Is to write one for the 2.7CRD" Lols! :rofl:

 

Drive that thing across the pond and I'll be glad to do a write up on it!

This is random but, I hope we meet someday.

Our home and my garage are welcome to anyone who wants to stop by. You're only 5.5 hours away! I'll fire up the smoker and have 8+ pounds of pulled pork ready when you show up!

For those talking about doing this project the 'easy' way - I'm darn near tempted to take a second look at mine. I do believe it's possible though I couldn't see how. If I can take a look and figure out the easy method, I'll feel like an idiot!

:tea:

 

This is random but, I hope we meet someday.

Also... When I had to do this I used method #3 and while it was a tight squeeze I found it quite manageable. I got one from the local dealer. I think it was 89 bucks but I could be wrong.

Good stuff.

 

Nice writeup - I had found a Youtube video that showed a similar process that I used.

 

Very good write up, however I am one of the guys that did #4 in under 30 minutes. 23" of 3/8" extensions with a swivel on the end. Once the bolt was out I pulled it from the engine bay by reaching back over the bell housing and installed the new one the same way. The swivel allows you to position the bolt at the angle to get it started and then you tighten it up. I cant imagine dropping a cross member or drive shaft to do the job...

 

You heard the man...Mr Hager is waitin' on you guys.....

 

Oh how I wish it were so easy...... Being a UK car, slight advantage that there are no pedals in the way - yippee. However, I can't get the sensor to budge. Stuck fast and now soaked in penetrating fluid. Next stop, heat!!!

 

I'll just throw it out there.. I'm 6' and only 135lbs.. It was near impossible to get my scrawny *** hand up in there to fish the sensor out and put the new back in.. I went through the access hole in floor to unbolt the sensor.. Fished it out from underneath then back in.. Had a second person help put the bolt in while I was underneath hold the sensor in place and also helped line up the socket to get bolt on straight.. As far as the interior I only pulled off the two dash panels and then the air duct.. Total job took less than an hour.

 

definitely saving this to my list of favorite threads, gotta do this later


thanks for the awesome write up

 

Nice wright up but it seems like a few extra steps? I replaced that crank sensor twice on my brother in laws WJ.

I was able to get my socket on the bolt from underneath with a few extensions, after I loosened the bolt I was able to reach from the engine side under the vehicle and grab the bolt and sensor with my hand. It was surprisingly easy to reach from there, loosened the bolt and pulled the sensor, installed the new one and hand threaded the bolt, and tighten. I had it replaced in 5mins. You do have to kind of wrap your hand around the bell housing and can be kind of tricky to get into the proper position to twist your hand like that but it can be done! I only dropped the bolt twice!

His Jeep was an 01 4.0 with the 242 transfer case, stock height.

 

I replaced one in my niece's 02 WJ with the 4.0 and it was rough I remember. I used a really long extension and a 7/16 wobble socket to get the bolt out. That was easy, the engine was still hot and I pulled the sensor out from where the exhaust come off of the engine and it was almost impossible reaching up through there even with my tiny hand's and arm's. It would have been somewhat easier if the engine and exhaust were cool but she was waiting on me to get it done. I finally got the sensor pulled out of the bellhousing and swung it to the other side of the tranny then unplugged it and plugged the new one up and swung it around to the other side and got it from the top and got it started back into the hole from the top side and got it into position and then took the extension and got the bolt started back into the bellhousing and tightened it up. I also remember slicing my hand on a part of the intake gasket sticking out on the back side of where the intake bolts to the head. If the jeep wasn't so freakin hot it would have been some easier but still not a walk in the park like the old XJ's and ZJ's were to swap out...

 

This should be sticky'd somewhere. Very good write up.

Good idea with the tape and the bolt too. This would be very helpful for the rear most bolts holding the 4.0 valve cover in place.

When mine failed Spring 2014 (?), the furthest i was able to get was removing that zinc/ chrome plated bracket. I ended up having to take it to a local mechanic down the road. $60 on top of the Mopar sensor. Could've been worse I guess.

 

Real good write-up with photos Chris! I realize nobody has posted in this thread in 1 1/2 years but a link for replacing the 4.0 crank sensor should be in the FAQ's!

While some may be able to reach clear up in there, and not remove the under-dash parts for crank sensor access, I've yet to see any write-ups how to do this. Again, post a link in the FAQ's to help other members.

 

Done! Thanks for the reminder.

 

You're welcome Chris and thanks for linking your write-up to the FAQ's.

 

As I posted in this other thread I started, these step-by-step instructions by ChrisHager have been really helpful to me. I've now gotten to the point where I have dropped in the new sensor, but am having trouble getting the bolt and shield back in place. I'm being extra careful not to drop them, so it's taking me a while. I've tried taping the bolt/shield to the socket and swivel joint, but getting it into position has been a real challenge. If anyone has any additional advice on getting the bolt in place, I'd love to hear it.

BTW, I wasn't able to get the new sensor in place working from under the dash, but I was able to do it by reaching down from above and placing it in the whole by feel. I'm not so confident that I would be able to get the bolt in place that way though because I don't think I could get it screwed in one-handed by feel.

I've also gotten under the Jeep to see about accessing everything from below, and like ChrisHager, I just can see how I could possibly reach it from there. I'm open to giving that another try as well if anyone has any useful advice or pictures.

 

I took the air intake cover/cap off and it gives you a few more inches to reach down from the top laying ontop of the engine. I could get that metal cap over the sensor, while my wife was in the jeep trying to steer the bolt on using a wobble, its very tough and ended up cutting the floor out a little.

It looked to be possible from below by unbolting the cable lever linkage for the transmission or transfer case, if you could get a socket in there that is the only thing in the way to get your hand up from the bottom and for sure could thread the bolt on.

 

I went through the floorboard. Take the access plate off and the bolt is darn near a straight shot.

There's a LOT of stuff to move/remove to get to it, and you'll need someone with smaller/skinny arms for the "reach behind the engine" part, but that's the only way I could get it. There was NO way to get at it from underneath...