Replacing: Camshaft Positioning Sensor

I am going to try and replace the CPS this weekend. I haven't done this before, but the check engine light came on and the CPS code came up.
So I am looking for any help. A write-up would be nice, but i might have to go buy a chilton's because i can't find mine. Hopefully it won't take too much :smsoap: ....

Any tips would also be appreciated. Also is there anything else i should check when i am working through this.

Thanks,

PBen

camshaft or crankshaft? if it's the crankshaft position sensor (commonly referred to somewhat incorrectly as the CPS) it's not hard, just time consuming. you'll need a bunch of extensions and a ujoint extension. it helps if you have a tcase drop, or can support and lower the transmission to give better clearance to fit your hand up to the sensor after the bolts are removed. I did mine in the parking lot at work (because it wouldn't start.. ) and it took me around 3 annoying hours of muttering "I can't believe this" and driving my car back to Pep Boys again for more extensions and sockets. knowing how to do it now... 15-20 minutes.

Oops, i made the mistake, it is the Camshaft Positioning Sensor...I put the wrong acronym.
THanks,
PBen

flash2pablo said:

I am going to try and replace the CPS this weekend. I haven't done this before, but the check engine light came on and the CPS code came up.
So I am looking for any help. A write-up would be nice, but i might have to go buy a chilton's because i can't find mine. Hopefully it won't take too much :smsoap: ....

Any tips would also be appreciated. Also is there anything else i should check when i am working through this.

Thanks,

PBen

Click to expand...

ahhhhhhhhhhhh i just did this!

my jeep pulled a no bus code on the dash and none of the gauges worked etc etc so a little research here and the CPS sensor, which is a magnet will simply fail - i have 98k so its about that time for stuff to start doing this

anyhow- it is about 80 dollars at the part store which sucks

i went to the junkyard and grabbed 2 just incase mine went out again...

i have 7 inches of lift which was nice b/c i can crawl under my jeep and see it easily - it is located on top of the tranny housing with 2 bolts - 11 mm each - the sensor goes down into the tranny and there is a plastic dustcover that you need to keep when you reinstall your new one - one the wiring side it simply is a molex/ plug and play clip that disconnects around your manifold. tb so its under the hood

so crawl under jeep, look at tranny facing the front of your jeep and it will be tucked inbetween body and the top of the tranny - the sensor is held by a slightly curved bracket which is held on by the two bolts

the chitlons has a great diagram in it

make sure when you get your new sensor to say you have a regular cherokee - not a grand - the two sensors a different ask me how i know:roll: parts people work long hours i guess and i think when i said cherokee he thought grand cherokee

so all in all i could get one now in 10 minutes out and 10 minutes in - i used almost 1.5-2 feet of extensions because there is no room inbetween the tranny and tunnel - oh and you might need a light to shine in there - duh

good luck if you want me to snap a pic holla

camshaft? ah crap well thats how you change a crank shaft sensor - bleh

this depends a lot on the year. The mounting of the cam pos. sensor changed somewhere between 93 and 95. I've done both types.

On a 93, you have to pull the distributor. It's a good idea to put the crankshaft at TDC, but whatever you do, make a careful mark on the distributor body to note the location of the rotor, and once the distributor is out, do not budge the engine. Now with distributor out, you punch out the roll pin that holds the gear on the bottom, and withdraw the shaft. The sensor is then accessible, and you can replace it, replace the shaft (oil it while you're at it), put the gear and pin back in, and then reinsert the distributor. Remember when doing this last thing that the helical gear will cause the rotor to turn a little as you put it in. So start it a little behind where you want it to end up, put it in carefully, and if the marks line up, bolt it down, put the cap back on the disty and if it starts right up, pop the cap off a small beer.

On a 95, the sensor is on a plastic plate, accessible by taking the rotor off. Replacement is obvious, and the job will take about one minute. Don't even pop the cap off that beer. You don't deserve it.

My Cherokee is a 2000 with 4.0. I should have thrown that out there first.

What was your code flash2pablo? My jeep crapped out a P0340 this evening, reading camshaft positioning sensor too. I need to get it fixed FAST before it gets towed. I went to several big name auto parts stores and no one can get one.. like there pattened or something. I've read through some posts and discovered that it is inside the distributor for later models. so thats a start. Should we (cps problem people) buy a whole new distributor or go to the junk yard for one or what the heck? Thanks... and good luck

96CheroKeeClassik said:

What was your code flash2pablo? My jeep crapped out a P0340 this evening, reading camshaft positioning sensor too. I need to get it fixed FAST before it gets towed. I went to several big name auto parts stores and no one can get one.. like there pattened or something. I've read through some posts and discovered that it is inside the distributor for later models. so thats a start. Should we (cps problem people) buy a whole new distributor or go to the junk yard for one or what the heck? Thanks... and good luck

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I got the one for my 95 at an auto parts store, but perhaps they changed it again. It might not be that much worse at a dealership, and almost certainly cheaper than a new distributor. I don't know how the 2000 differs, and haven't even bothered to look under the cap of my 99, but if it's the same design as the 95, it's really dead simple to replace.

In the meantime, again not sure whether this will work on later ones, but both the 93 and 95 can be teased into starting this way: Turn on the ignition, without cranking, and leave it on. Now unplug and replug the distributor harness. You can then crank the engine and it will start. It will not restart without doing the same thing again, and it will not run terribly well, because the injection timing is off, but it will run. When I did this with the 95, it also threatened to overheat after about 5 miles, but it got me home.

I tried unplugging and repluging the harness on my 97 just to get it home, and it wouldn't start with just that. After some discussion with one of the smarter auto parts guys about why no parts store could get a "camshaft positioning sensor" he told me that it was probably the "pickup" that I was needing. So, I took the $40 pickup and replaced it in seriously 5 min and it fired right up.

All I did was disconnect the plug wires, unscrew the 2 screws, pull the piece that spins on top of the shaft off, remove and replace the black circular pickup with the harness and plug the new one back in. I didn't have to pull the shaft or anything like that. Heres a crappy camera phone pic but it does the job...

96CheroKeeClassik said:

I tried unplugging and repluging the harness on my 97 just to get it home, and it wouldn't start with just that. After some discussion with one of the smarter auto parts guys about why no parts store could get a "camshaft positioning sensor" he told me that it was probably the "pickup" that I was needing. So, I took the $40 pickup and replaced it in seriously 5 min and it fired right up.

All I did was disconnect the plug wires, unscrew the 2 screws, pull the piece that spins on top of the shaft off, remove and replace the black circular pickup with the harness and plug the new one back in. I didn't have to pull the shaft or anything like that. Heres a crappy camera phone pic but it does the job...

Click to expand...

Yep. that's the same as on my 95. Somebody was thinking when they changed that design. Too bad they must have changed some setting in the computer when they went to OBDII though, because that unplug trick worked for me on both the older ones I had fail.

That is the same on my 94 also although I did not change mine. I had the joy of a distributor cap screw snapping off in the distributor. I drilled it out and now have a through bolt and nut. I think it was because the woman asked me how long and I answered 10 minutes to change the cap and rotor lol. Guess i had to be proven wrong again by her lol
:gee:

Yep, That was the same code that mine had, but i also had code P0301 Cylinder misfire. But i am guessing it is because of the Camshaft sensor.
The only thing that kinda confuses me is that most people who have had a problem with the camshaft positioning sensor have not been able to start their XJ's. Mine has not had a problem starting, and i have driven it over 200 miles with since check engine light, because i had to drive it home.

I am going to get a new pickup tonight hope this fixes it.

Thanks for the info and pic's.

PBen