Quote from SoonerCentral on December 26, 2014
Here’s the easier way with Torque:

– Buy the app, just do it!
– Get it connected and working with your ODB2 adapter.
– Create a custom PID. The critical parts are 221301 as the Mode/PID string, a negative minimum value (-100 should be fine), and the equation is ((Signed(A)*256)+B)*0.024
– Add a real time display to show this PID along with the engine RPM.

Rev engine over 1k, adjust within +/- 2.0, slightly tighten, and retest. I say slightly, because it’s entirely true that the mere act of doing so will generally change the setting. On a 5.7, with the wiring harness in the way…

*********************************

OK, I just bought Torque Pro, and I followed (and double-checked) the steps above.

If I use the Edit Custom PID method and click Test at the bottom of that screen, the equation returns a value of 7F2213010011.

I set up a real time display for the custom PID, but it just sits at zero, no matter what I do. I edited that display to include 3 digits, so it displays 0.000, but it never changes. Revs (rpm’s) are right next to it, and they are working properly.

1996 5.7l vortec.

At this point, I I tried this with OBD Header set at blank, also set at ‘Auto’, both provide the same result.

My interface is a blue chinese Jtron ELM327 Mini that I have had for about 4 years pr so.

I’m using Torque Pro on an android phone.

I’m guessing that the 0011 trailer on the Test Response may be valid data. When I have time, I will test this theory by moving the distributor cap and doing another test to see if the two end values change.

I am not getting a code. This is more of a thing where I have done the intake gasket job many years ago, and also changed a rotor many years ago, but I have never had a scanner check of distributor cap alignment. I’d like to check it and adjust it if necessary, plus I just ordered a new cap and rotor because my rig now has 225K miles, so I want to replace those components and then set the new distributor as close to 0° as I can.

Bottom line – for me, the realtime display does not work. Maybe the Test response is a valid response.

This thread is interesting, but it does not really provide a full suite of usable data for a new reader.

This thread provides “critical parts” for the custom PID, but it leaves me wondering about Scale Factor, Unit Type, OBD Header, Diagnostic Start Command, and Diagnostic Stop Command. Are we really to just leave these blank?

Also, if one performs a test and receives the response described above, are those last two values something that one would consider valid, usable responses?

Thanks!

Thanks Capp, I will try this.

I don’t know what VPW means.

I did try the 6C10F1 header. I made sure that the engine was stuck at 1100 rpms before starting Torque. I tried the test function, but got the same invalid response as before.

I get a lot of valid functions from my kit. It will read correct rpms, scan codes, erase codes, etc, etc.
It just won’t work for CMPRET with the formulas and methods discussed here.

I’m open to other ideas or suggestions, because I would love to get this simple capability of properly aligning the distributor, whether it be with Torque or some other app.

All of my reading suggests that a 96 vortec in a Yukon is the same 0+2° spec as other years.

Thanks.

I got it to work with DashCommand.

.95 for the app. .95 for the special GM PID’s.

It works fine with my 5yr old chinese ELM327 Mini bluetooth interface.

I found an old thread on the palmerperfomance.com forum. It tells how to use the free evaluation version of DashCommand to see whether the app will support the Camshaft Retard Offset PID (aka CMP, aka Cam Retard) for your specific vehicle.

That’s how I started. I installed the free DC app, then entered the basic details for my vehicle, then the following steps:
1.) Go to the Data Grid View.
2.) Tap PIDs.
3.) Tap Add PIDs
4.) Tap the little 3-dot menu button at the bottom right.
5.) Tap Sort PIDs.
6.) Sort by Manufacurer.
7.) Tap GM.
8.) Look for the GM.ENGINE.CR pid. If it is present in the list of available PID’s under the GM heading, then supposedly DashCommand will display that value after you buy the app and the extended code set. If this particular PID is not present in the list, then there is no reason for you to buy the app, because the app doesn’t support that code for your vehicle.

For me – it was the 3rd item in the list. So I bought the app, then I bought the extended GM code set.

Then I clicked the Gauges item in the home menu, and repeated a similar “sort by manufacturer” process to add the PID from the extended set to the main app. Then I set up a CR dial gauge with digital window, right next to a similar gauge for RPM. Then I started my Yukon and tapped the Connect button. Holy shit! There it was! -4.8°.

I tapped the back button and then the disconnect button.

Then I changed all my plugs, wires, my distributor cap, and rotor. While the cap was off, I loosened the distributor hold-down bolt, to where the distributor was free to turn, but snug, not sloppy. Then I put everything back together and set the distributor close to where it was before I started the job (based on a cell-phone pic). Then I started the engine (air intake assy still off the vehicle). I opened the throttle slightly by hand and stuck a thin piece of cardboard between the throttle-stop screw and its related contact arm on the throttle pulley assy and then let it shut on the cardboard, pinching it in place. This caused the motor to run at 1500rpm. Then I tapped the Connect button on the DC app, and pulled up my gauge screen. -9.4°

What I learned at this point was that the motor will start if your distributor is 7.4° out of spec, and also that it won’t necessarily throw a code right away, because the only codes I got were MAF codes related to the fact that the MAF sensor was unplugged and laying on the floor across the garage.

Anyway, I twisted the distributor CCW, and sure enough, the CR reading came around to with the 4° spec window. So I kind of eyeballed the position of the distributor that was close to 0°, then I shut off the motor, bellied up on some folded towels on the fan shroud, turned the distributor to where I thought it should go, and then commenced the battle of tightening that damn hold-down bolt while laying on the motor and holding the distributor in the position I thought it should be. I tightened the bolt just past snug, then fired up the motor and restarted DashCommand.

I got 0.1°. LOL. I never get lucky like that, but I did today.

That’s it. I tightened the hold-down bolt to 25ft lbs, buttoned everything up and went for a spin. On the hwy, it was cruising at 55mph at ~1500 rpms, and I tapped the connect button on DC, and presto, I was holding a fluctuating CR value of between 0 and 0.1°. Job done.

It was weird in a way. I had to do a lot of reading to try to find something that might work, and then all of a sudden, there it was.

Motor sounds smooth. No more tiny stumble here and there. Maybe it was the new spark plug wires and cap and rotor. Maybe it was the CR. maybe it’s both.

Thanks for the feedback here.

Funny to chase a code this hard for a 20yr old vehicle.

Oh, one more thing: Dash Command is pretty good, but it is not an intuitive interface. I’m do some webdev work. Intuitive processes are elemental to good design. DC is pretty powerful, but it’s damn clunky. If I hadn’t found that old thread about sorting by manufacturer to see a code that is otherwise not displayed anywhere, and if I hadn’t figured out that you have to tap a little obscure menu button before you can do the search, then DC would have been a bust for me. It has lot’s of bells and whistles, but it has no intuitive flow. Torque is a better design, but it ain’t got no CMP.

Good luck!

Bump hoping for some answers…

Will Torque parse the 2A request correctly?

Assuming the given hex response example…

……………………….A…B…C…D…E…F…G
6C F1 10 6A 09 00 00 37 76 FF CE 4F
R0

is typical and can be parsed correctly…

I would test:

((Signed(E)*256)+F)*(1000/15625)
((Signed(N4)*256)+N5)*(1000/15625)
((Signed(R9)*256)+R10)*(1000/15625)

((Signed(E)*256)+F)*(1/16)
((Signed(N4)*256)+N5)*(1/16)
((Signed(R9)*256)+R10)*(1/16)

(I drive an OBDI Jeep and can’t test this
further without help).

Header: 6C10F1
Mode/Pid: See interesting reading links above (2A…)
Long Name: Camshaft Retard Offset (DPid)
Short Name: Cmpret
Equation: See test equations above.
Units: Degrees (°)
Scaling: x1
Min: -24.0
Max: 24.0
Diagnostic Stop/Start: Leave blank.

Rx addressing may work if Torque cannot
parse the other addressing types correctly.

I am also wondering if…

37 76 is engine rpm?

((C*256)+D)*(1/8) = 1775 ?
((N2*256)+N3)*(1/8) = 1775 ?
((R7*256)+R8)*(1/8) = 1775 ?

4F is engine temperature?

G*(9/5)-40 = 102 °F ?
N6*(9/5)-40 = 102 °F ?
R11*(9/5)-40 = 102 °F ?

Notes:

Rx addressing shown is for headers on (ATH1)
and will need to be adjusted by -3 if headers are
off (ATH0)…

………….A…B…C…D…E…F…G
6A 09 00 00 37 76 FF CE 4F
R0

A, B… and N0, N1… addressing is off by
a byte as suggested in later posts so Rx
addressing should be used until corrected.

Variable A (N0) is actually pointing to B (N1), etc.
True data byte A is currently unaddressable
without using Rx addressing.

Edited.

Quote from DCS on September 16, 2016
I got it to work with DashCommand.

.95 for the app. .95 for the special GM PID’s.

It works fine with my 5yr old chinese ELM327 Mini bluetooth interface.

I found an old thread on the palmerperfomance.com forum. It tells how to use the free evaluation version of DashCommand to see whether the app will support the Camshaft Retard Offset PID (aka CMP, aka Cam Retard) for your specific vehicle.

That’s how I started. I installed the free DC app, then entered the basic details for my vehicle, then the following steps:
1.) Go to the Data Grid View.
2.) Tap PIDs.
3.) Tap Add PIDs
4.) Tap the little 3-dot menu button at the bottom right.
5.) Tap Sort PIDs.
6.) Sort by Manufacurer.
7.) Tap GM.
8.) Look for the GM.ENGINE.CR pid. If it is present in the list of available PID’s under the GM heading, then supposedly DashCommand will display that value after you buy the app and the extended code set. If this particular PID is not present in the list, then there is no reason for you to buy the app, because the app doesn’t support that code for your vehicle.

For me – it was the 3rd item in the list. So I bought the app, then I bought the extended GM code set.

Then I clicked the Gauges item in the home menu, and repeated a similar “sort by manufacturer” process to add the PID from the extended set to the main app. Then I set up a CR dial gauge with digital window, right next to a similar gauge for RPM. Then I started my Yukon and tapped the Connect button. Holy shit! There it was! -4.8°.

I tapped the back button and then the disconnect button.

Then I changed all my plugs, wires, my distributor cap, and rotor. While the cap was off, I loosened the distributor hold-down bolt, to where the distributor was free to turn, but snug, not sloppy. Then I put everything back together and set the distributor close to where it was before I started the job (based on a cell-phone pic). Then I started the engine (air intake assy still off the vehicle). I opened the throttle slightly by hand and stuck a thin piece of cardboard between the throttle-stop screw and its related contact arm on the throttle pulley assy and then let it shut on the cardboard, pinching it in place. This caused the motor to run at 1500rpm. Then I tapped the Connect button on the DC app, and pulled up my gauge screen. -9.4°

What I learned at this point was that the motor will start if your distributor is 7.4° out of spec, and also that it won’t necessarily throw a code right away, because the only codes I got were MAF codes related to the fact that the MAF sensor was unplugged and laying on the floor across the garage.

Anyway, I twisted the distributor CCW, and sure enough, the CR reading came around to with the 4° spec window. So I kind of eyeballed the position of the distributor that was close to 0°, then I shut off the motor, bellied up on some folded towels on the fan shroud, turned the distributor to where I thought it should go, and then commenced the battle of tightening that damn hold-down bolt while laying on the motor and holding the distributor in the position I thought it should be. I tightened the bolt just past snug, then fired up the motor and restarted DashCommand.

I got 0.1°. LOL. I never get lucky like that, but I did today.

That’s it. I tightened the hold-down bolt to 25ft lbs, buttoned everything up and went for a spin. On the hwy, it was cruising at 55mph at ~1500 rpms, and I tapped the connect button on DC, and presto, I was holding a fluctuating CR value of between 0 and 0.1°. Job done.

It was weird in a way. I had to do a lot of reading to try to find something that might work, and then all of a sudden, there it was.

Motor sounds smooth. No more tiny stumble here and there. Maybe it was the new spark plug wires and cap and rotor. Maybe it was the CR. maybe it’s both.

Thanks for the feedback here.

Funny to chase a code this hard for a 20yr old vehicle.

Oh, one more thing: Dash Command is pretty good, but it is not an intuitive interface. I’m do some webdev work. Intuitive processes are elemental to good design. DC is pretty powerful, but it’s damn clunky. If I hadn’t found that old thread about sorting by manufacturer to see a code that is otherwise not displayed anywhere, and if I hadn’t figured out that you have to tap a little obscure menu button before you can do the search, then DC would have been a bust for me. It has lot’s of bells and whistles, but it has no intuitive flow. Torque is a better design, but it ain’t got no CMP.

Good luck!

This worked for me thanks!!

I believe the form of the equation given is
correct but the slope of 0.024 is not. Since
zero is ideal it still works with any slope…
just can’t believe the degrees reading away
from zero without the correct slope.

A two byte signed equation produces a result
from -32768 to 32767. Not sure treating each
byte as a signed value to itself would work
properly. For instance…

In the case of Signed(A)+Signed(B)

FF FF would result in -1 and -1 which when
added together becomes -2.

In our case… ((Signed(A)*256)+B)

FF FF would result in (-1*256)) and 255 which when
added together becomes -1.

So far there are two possible pids for this parameter
but only one has been tested to date.