My first TJ 2.4 has a persistent P0016 code

[Gui_06TJ]

Hi Everyone,

I just got my very first Jeep Wrangler after a long wait: a 2006 TJ SE manual 2.4L 4-cyl, 92k miles, 4 owners. At this point, I could only enjoy 3 weeks of intense labor trying to solve a persistent P0016 + limp mode issue.

I got it from a neighbor who put some time into it but never really finished the job. I tried to fix it myself through Gemini and ChatGPT. I made some progress, but now I need help from the real experts - YOU.

The TJ had 2 main issues when I got it:

1. Check gauge light ON and no oil pressure reading on the cluster;
2. Check engine light ON with P0016 code (camshaft and crankshaft correlation issue)

For #1 - I checked oil level and condition (both were OK), changed oil and filter as per specs, and replaced the cheap oil pressure sensor (which had a major leak at the connector) with an OEM Mopar unit. This fixed the gauge and restored oil pressure reading on the cluster.

For #2 - P0016 + limp mode - still there:

a) Timing: I checked and adjusted timing - the belt and tensioner had apparently been replaced, but were not properly done. I aligned crank and camshaft marks as well as belt tension as per specs/recommendations from this forum. I cleared codes and drove the Jeep; P0016 came back, but timing is still correct.

b) Camshaft sensor: previous sensor was pretty scored/damaged (by the tone wheel for sure, perhaps due to wrong air gap). Tone wheel looks OK, not bent. I replaced the camshaft sensor with a cheap Amazon one (did not solve P0016) and finally with an NGK/NTK unit with the correct air gap (0.7mm or 0.030”).

c) Crankshaft sensor: installed OEM Mopar sensor. The previous one was not entirely seated (had a gap of around 2mm or more).

d) Visually inspected wiring, which looks OK, with no obvious evidence of issues.

e) I removed all the poorly installed electrical components added by previous owners (air horn, 2 LED bars), since they were not properly installed. I checked ground points (firewall, hood) and cleaned contacts and battery terminals.

f) Disconnected and reconnected battery terminals a few times, and even let it sit overnight as per some suggestions (“clear the memory”… although I am not sure about this one), but P0016 always comes back.

So, the TJ throws a P0016 in different ways/occasions:

• sometimes only when crossing the 3,000 RPM mark
• sometimes it idles for a few minutes and throws the code at 1000 RPM
• sometimes it revs to 4000 or 4500 RPM (either parked or in motion) with no code, but throws it later while cruising

I feel I have done all I could. I am totally fine with putting more labor into it, but I decided to stop replacing parts randomly since this is getting expensive with no indication the P0016 will actually be addressed.

Anyone here able to shed some light and help me get this solved? Appreciate your help!

 

[Chris]

Hi Everyone,

I just got my very first Jeep Wrangler after a long wait: a 2006 TJ SE manual 2.4L 4-cyl, 92k miles, 4 owners. At this point, I could only enjoy 3 weeks of intense labor trying to solve a persistent P0016 + limp mode issue.

I got it from a neighbor who put some time into it but never really finished the job. I tried to fix it myself through Gemini and ChatGPT. I made some progress, but now I need help from the real experts - YOU.

The TJ had 2 main issues when I got it:

1. Check gauge light ON and no oil pressure reading on the cluster;
2. Check engine light ON with P0016 code (camshaft and crankshaft correlation issue)

For #1 - I checked oil level and condition (both were OK), changed oil and filter as per specs, and replaced the cheap oil pressure sensor (which had a major leak at the connector) with an OEM Mopar unit. This fixed the gauge and restored oil pressure reading on the cluster.

For #2 - P0016 + limp mode - still there:

a) Timing: I checked and adjusted timing - the belt and tensioner had apparently been replaced, but were not properly done. I aligned crank and camshaft marks as well as belt tension as per specs/recommendations from this forum. I cleared codes and drove the Jeep; P0016 came back, but timing is still correct.

b) Camshaft sensor: previous sensor was pretty scored/damaged (by the tone wheel for sure, perhaps due to wrong air gap). Tone wheel looks OK, not bent. I replaced the camshaft sensor with a cheap Amazon one (did not solve P0016) and finally with an NGK/NTK unit with the correct air gap (0.7mm or 0.030”).

c) Crankshaft sensor: installed OEM Mopar sensor. The previous one was not entirely seated (had a gap of around 2mm or more).

d) Visually inspected wiring, which looks OK, with no obvious evidence of issues.

e) I removed all the poorly installed electrical components added by previous owners (air horn, 2 LED bars), since they were not properly installed. I checked ground points (firewall, hood) and cleaned contacts and battery terminals.

f) Disconnected and reconnected battery terminals a few times, and even let it sit overnight as per some suggestions (“clear the memory”… although I am not sure about this one), but P0016 always comes back.

So, the TJ throws a P0016 in different ways/occasions:

• sometimes only when crossing the 3,000 RPM mark
• sometimes it idles for a few minutes and throws the code at 1000 RPM
• sometimes it revs to 4000 or 4500 RPM (either parked or in motion) with no code, but throws it later while cruising

I feel I have done all I could. I am totally fine with putting more labor into it, but I decided to stop replacing parts randomly since this is getting expensive with no indication the P0016 will actually be addressed.

Anyone here able to shed some light and help me get this solved? Appreciate your help!

Not sure about the 2.4, but on the 4.0 when you install a new CPS you have to do a re-learn procedure on a DRB III or an OBDII scan tool with the proper features.

I'd suggest checking out the FSM and seeing if that's something you need to do on your 2.4.

You can find the FSM for free here.

 

[Gui_06TJ]

Thanks Chris, I’ll dig into the FSM for the 2.4L. My OBD scanner is a Autel Maxilink ML629 but does not recognize the jeep… I will share my findings here shortly

 

[Gui_06TJ]

Here's an update: I took the jeep for a full diagnostics at the Jeep dealer (NJ) and after finding the right computers to run the trouble codes and update PCM/relearn (new sensor was installed). The error code moved from P0016 (with limp mode triggered at 3000 rpm) to P0344 (with limp mode triggered at 2000 rpm)... the verdict is: the tone ring has marks/scratches on its back, visible with the camera. And the part is not in stock and could not be found. Does anyone know who could remanufacture this part (tone ring) or was able to straighten/sand and make it work?

 

[GoldenGorilla]

That 2.4L was shared with a huge range of Dodge and Chrysler vehicles. The block is a unique casting but the running gear generally isn't. Cross-ref to manual Chrysler 200, PT Cruiser, Neon, Jeep Compass?