Will the Thinkdiag also provide the cam/crank difference? It’s $84 instead of $120 for the Thinkdiag2
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Using the DRB III to Calibrate a New Cam Sensor in the 4.0 Engine (2000-2006)
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Will the Thinkdiag also provide the cam/crank difference? It’s $84 instead of $120 for the Thinkdiag2
no idea. I saw that as well but I had seen the Thinkdiag2 mentioned specifically here so that's what I bought.
Do you plan to do the relearn via the battery trick after dialing in the difference?
I believe the thinkdiag2 will trigger the relearn as well, so I'll probably just use that so I don't reset ALL the learned stuff like the fuel trims.
Also, to be clear, this is mostly just me tinkering. I have no cam/crank code and still have factory cam and crank sensors and factory OPDA, but I have an 06 and a crown OPDA in my parts box, so I consider it a possible eventuality. I'll take a look at the cam crank difference and whatever else I can see and do and probably post a thread about it, but right now I don't need to do the relearn so I probably won't.
Hmmm. I suspect it's got the wrong equation to decode from hex.
6553.5 just happens to be what you get from a maxed out 16 bit data type scaled by 0.1x. That's a pretty damn big coincidence.
Mine came in yesterday but I haven't tried it yet. I'll have some tinkering time tomorrow and will report what I find.
I think freedom_in_4low is on the right track. When I was fiddling around with mine I was trying to get the Cam/Crank Difference as close to zero as possible. I had the engine running and was monitoring the Cam/Crank Difference and delicately rotating the OPDA. I got down to a difference of 0.5 and thought I could better. I rotated it just a little bit more and the number changed to a 65xx.xx number (sorry I didn't take of pic of what the actual number was). So I realized I went the other side of zero......I rotated the OPDA back the other direction until I got back to the 0.5 degree difference and locked it down there.
Hope that makes sense.
Hope that makes sense.
Very interesting. It's behaving exactly like a signed/unsigned data type mismatch.
"Two's complement" is an encoding method that allows for a signed (positive or negative) integer to be represented by an unsigned (always positive) integer. Basically the bottom half of the number space is unchanged, but the top half is for the negatives. When you go from zero to -1 it wraps around to the max value.
This is an example of how it works with 8 bits, but extending it to 16 bit, 1 through 32767 = 1 through 32767, 32768 = -32768, and 65535 = -1
So it looks to me like the PCM is providing a two's complement signed value that thinkdiag2 is interpreting as an unsigned integer, causing negative values to wrap back into the top end of the space.
I adjusted my difference to .20 but the relearn would not budge from 6553.5 using the device or touching the cables.
I then adjusted the difference out to .70. At first, I couldn’t get the relearn to budge with the device or by touching the cables.
After multiple tries, the relearn changed to .10 degrees.
Thanks for helping me get things dialed in.
For anyone having trouble with the relearn on an 05/06, I was able to dial in the relearn more after doing unrelated TSB wiring for the o2 heaters.
For the manual relearn this time around, I followed similar advice which was to disconnect only the positive cable, then touch the positive and negative cables for 30 seconds. Then reconnect the positive cable to the battery, turn key to ignition on, turn headlights on then headlights off, and finally turn the key to off.
FWIW, the relearn updated after following those instructions.
For the manual relearn this time around, I followed similar advice which was to disconnect only the positive cable, then touch the positive and negative cables for 30 seconds. Then reconnect the positive cable to the battery, turn key to ignition on, turn headlights on then headlights off, and finally turn the key to off.
FWIW, the relearn updated after following those instructions.
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How did you move the OPDA cuz I’m having same issue. Please describe process. Thanks!
Did this procedure that you mentioned, so far all good! Thanks for the info brother!
Didn’t work, Cel came back on for P0344 and P0016, so next step is to replace OPDA.
You dialed in the cam/crank difference and did the relearn and it still came back? Lame
Hopefully it’s just a bad cam or crank sensor or bad OPDA. (Hopefully it’s not a timing chain issue)
After you find the issue, it might be worth rechecking the difference and doing the relearn. Best of luck
I'd just pull the OPDA and check the gears but frankly unless you are having issues with squealing or the like it's a waste of time.
Guarantee it's a stretched timing chain with those codes and it's moved the timing past where the ECU can compensate. The timing chain in these isn't that bad a job as its not an OHC engine. If you go down this path definitely do the water pump and crank pulley at the same time.
I had an interesting situation yesterday. I drove about 230 miles in 90 degree weather after performing the relearn process of positive lead disconnected touching the negative post and cable for 30 second and then reconnecting the positive lead, turn the key on,(not the engine), then lights on and off then the key off. After I started the engine, everything seemed to work correctly but after an additional 60/70 miles or so in that weather the engine light came back on. As I went up a hill on the highway, the jeep started to buck and cut out as I put a load on it. In the last 8000 miles, I've changed out the Cam, Crank and OPDA . I kept using the OEM cam sensor with a new Crown OPDA and didn't use the Crown sensor that came with it. Since I continue to have issues, my guess at possible causes might be the OEM Cam sensor finally after 180K, is giving out; the OEM PCM is affected by the high heat. I don't know! Is there a way to test a cam sensor and/or the PCM to see if they are working correctly? Initially, I chose not to spend ~$500 on a new PCM from the guy down in Florida. If anyone has comments or other ideas, I'd like to hear them. Thanks! I just received my new ThinkDiag2, today. Made if I figure out how to use that, it will be helpful!!
Did you dial in the cam/crank difference before doing the relearn? Maybe that will help idk but worth a try imo.
I found the ThinkDiag2 to be a little annoying at first, but it’s tolerable (much faster) if you choose the system you want instead of all selecting the all systems scan. Then choose PCM at the top, which takes you to a list of items where you will check the cam/crank difference. Dial in the difference and then do the relearn. You can have the device do the relearn but I never saw the relearn update using the device so I did it manually.
I learned that it was faster to unplug the device and start over rather than try to back up to the previous page if I selected the wrong page (device lag annoyed me).
I don’t have the device with me or I’d go through the steps in more detail.
Also, in the beginning VIN verification page, select the Chrysler/Jeep/Dodge option and manually enter your year. The device will then grab your VIN from the PCM.
No I didn't dial in the cam/crank difference before doing the relearn as I thought I had that done correctly when I installed the OPDA. Also, I'm really not sure how one "dials in the cam/crank difference". If I was back in the 70's trying to get the max dwell degree out of my car with points, I could do the really well! Maybe today using the ThinkDiag2 is similar to using a dwell meter!!?? Thank you for your comments. I'll do a little more homework.
I dialed in the difference so that it was less than than 0.8* but at least 0.5*…by turning the loosened OPDA and watching the difference using the device app on my phone. After tightening the OPDA back down with a reading of 0.7*, I did the manual relearn.
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