97 TJ 4.0 camshaft position sensor replacement

Mud Mixer

Mud Mixer

Member
Supporting Member
Joined
Feb 1, 2019
Messages
59
Location
Sunny South, Florida
Symptoms:
  1. Hard to start, harder to start under 50F.
  2. Tach needle would go crazy right before stalling. Anytime, any speed/rpm.
  3. Wouldn't restart hot. Let cool for 10 minutes to restart.

Pulled codes via odometer/ keyswitch method. Code 54.

Pulled distributor and rotor to reveal CPS. Some parts houses call it a pickup. It's the plastic plate with 3 wires
75940
 
  • Like
Reactions: Chris
Now is a good time to ensure the distributor retaining bolt is snug. Mine was loose, hence the oil weepage seen in the first photo. A 1/2" crowsfoot and a long extension was all that was needed to put a half turn on the bolt. It's easier to do this before installing the CPS because the wires are in the way if you use a crowsfoot. Drop the CPS in place, don't forget the rotor, put the cap on.

I disconnected the battery for 2 minutes to reset the codes. They did not reset. Had to disconnect it 10 minutes to reset. 5602 7023 is the Mopar part number for the CPS

Results:

Starts up in 1/3 of the time.
Runs stronger with the AC on than it did without it before the fix (It's in the 80's here in S.Fla in February) .
I can do 70+ in 5th with the AC on with crappy 3:07 gears (2100 rpm).

Total time: less than an hour. If I had to do it again, probably 10 minutes

Skill level: If you know which way to turn a screwdrive, you can do this.
 
  • Like
Reactions: Blondie70, Jerry Bransford, RobertJ and 1 other person
Mud Mixer said:
Symptoms:
  1. Hard to start, harder to start under 50F.
  2. Tach needle would go crazy right before stalling. Anytime, any speed/rpm.
  3. Wouldn't restart hot. Let cool for 10 minutes to restart.

Pulled codes via odometer/ keyswitch method. Code 54.

Pulled distributor and rotor to reveal CPS. Some parts houses call it a pickup. It's the plastic plate with 3 wiresView attachment 75940
Click to expand...
Thank you
 
Mine starts fine when cold, then stalls out once warmed all the way up… Already ordered a Crank position sensor… could it instead be the camshaft sensor?
 
Wasn’t the Crank position sensor apparently… What should I try now? Camshaft position sensor?
 
tworley said:
If it is running great when cold and then begins to stumble when you reach temp it is likely an 02 sensor. Do you know when they were last changed?
Click to expand...

That would be my first thought, but the upstream O2 is darn near brand new,may be 6 months old and yes it’s the recommended NGK one. I didn’t change the downstream one because that one is only there to monitor if the cat is working properly.
 
tworley said:
If it is running great when cold and then begins to stumble when you reach temp it is likely an 02 sensor. Do you know when they were last changed?
Click to expand...

So, never got a CEL, and when I did the key trick I only got codes 12 and 55, which are just saying that the battery has been disconnected recently and end of codes.

Well I was a bit suspicious of this, so I took out my hptuners setup and pulled code P0351… Thinking camshaft sensor. What are your thoughts (before I spend another $100 or so)? Also, having trouble finding a Mopar one so help would be appreciated.
 
DWR said:
So, never got a CEL, and when I did the key trick I only got codes 12 and 55, which are just saying that the battery has been disconnected recently and end of codes.

Well I was a bit suspicious of this, so I took out my hptuners setup and pulled code P0351… Thinking camshaft sensor. What are your thoughts (before I spend another $100 or so)? Also, having trouble finding a Mopar one so help would be appreciated.
Click to expand...
When my camshaft or ignition pickup coil went I was throwing code. Its been a number of years since Ive had the issue but I do remember the research I did said the CPS shares the same code as the CAM (At least on the 97 model). I had somewhat similar issues in that it ran fine when cold, but it would skip/miss/hesitate after awhile. The problem was that it was very intermittent. I did replace the CPS sensor based on the code and saw no improvement, since the two share the same code I replaced the CAM afterwards and had success. That was 70k miles ago.
 
  • Like
Reactions: DWR
tworley said:
When my camshaft or ignition pickup coil went I was throwing code. Its been a number of years since Ive had the issue but I do remember the research I did said the CPS shares the same code as the CAM (At least on the 97 model). I had somewhat similar issues in that it ran fine when cold, but it would skip/miss/hesitate after awhile. The problem was that it was very intermittent. I did replace the CPS sensor based on the code and saw no improvement, since the two share the same code I replaced the CAM afterwards and had success. That was 70k miles ago.
Click to expand...
Thank you good sir! I’ll get a CAM/ignition pickup sensor ordered soon. Finally found a Mopar one…but as always, it isn’t cheap.
 
So… just put the new camshaft position sensor/distributor pickup in… was letting the jeep idle in the driveway but it shutoff still, interestingly a bit before it hit full temp with the new sensor. Can restart but shuts back off shortly afterward.

On a side note… I think the amazon seller pulled a fast one on me. Was supposed to be a Mopar sensor, came in a Mopar box… but it doesn’t have the number stamped on it like the one I pulled out

image.jpg



Can anyone confirm that newer Mopar sensor still have that stamped in?
Also, I’ve seen a couple places where people said the NAPA one is actually good… but for the later models. Can anyone confirm this for the early style?
 
cleverploy said:
+1 following. I'm dealing with the exact same issue for my 97 TJ Wrangler 4.0L. I think I just got burned by the same Amazon seller.
Click to expand...

Hate to hear that man, I ended up returning it and cleaning up the old. Never ended up buying another one because all my issues went away when I disconnected, cleaned, and reconnected the main spark coil and it’s connection to the ecu.
 
Top Bottom
Back