Spark A is occurring when cylinder 4 is at TDC instead of 1

[opel]

I have scoped the engine to confirm that Spark A is firing when Cylinder #4 is at TDC. The problem has now been reproduced on another vehicle by SymTechLabs.

Channel #1 (red) is Cam signal
Channel #2 (yellow) is Spark A

[opel]

[UnaClocker]

If you can run the MS3 1.0.3 firmware, you can fix this yourself. Download the source, open "ms3_ign_wheel.c" in a text edittor, Find this section:

Code: Select all

   /* ----------------------  420A/NEON MODE ------------------------ */
    } else if (spkmode == 5) {
        flagbyte5 |= FLAGBYTE5_CRK_DOUBLE;

        deg_per_tooth[0] = 200;
        deg_per_tooth[1] = 200;
        deg_per_tooth[2] = 200;
        deg_per_tooth[3] = 1200;
        deg_per_tooth[4] = 200;
        deg_per_tooth[5] = 200;
        deg_per_tooth[6] = 200;
        deg_per_tooth[7] = 1200;

        smallest_tooth_crk = 60;        // now 6.0 deg, was 20.0 deg
        smallest_tooth_cam = 150;
        trigger_teeth[0] = 5;
        trig_angs[0] = -1110 + tmp_offset;      // 69 BTDC (on next event) = 111ATDC
        trig_angs[1] = -1110 + tmp_offset;      // 69 BTDC (on next event) = 111ATDC

        if (((ram4.spk_mode3 & 0xc0) == 0x80) || (ram4.spk_conf2 & 0x08)) {      //if COP mode or use cam then double up pattern
            flagbyte5 |= FLAGBYTE5_CAM;
            deg_per_tooth[8] = 200;
            deg_per_tooth[9] = 200;
            deg_per_tooth[10] = 200;
            deg_per_tooth[11] = 1200;
            deg_per_tooth[12] = 200;
            deg_per_tooth[13] = 200;
            deg_per_tooth[14] = 200;
            deg_per_tooth[15] = 1200;

            trigger_teeth[1] = 9;
            trigger_teeth[2] = 13;
            trigger_teeth[3] = 1;
            trig_angs[2] = -1110 + tmp_offset;  // 69 BTDC (on next event) = 111ATDC
            trig_angs[3] = -1110 + tmp_offset;  // 69 BTDC (on next event) = 111ATDC
            no_triggers = 4;
            no_teeth = 16;
            cycle_deg = 7200;
        } else {
            trigger_teeth[1] = 1;
            no_triggers = 2;
            no_teeth = 8;
        }
        last_tooth = no_teeth;

        if (num_cyl != 4) {
            conf_err = 17;
        }


Specifically, this part:

Code: Select all


            trigger_teeth[1] = 9;
            trigger_teeth[2] = 13;
            trigger_teeth[3] = 1;


James, feel free to correct me if I'm interpreting this wrong, but I think you need to change this section to:

Code: Select all

            trigger_teeth[0] = 13
            trigger_teeth[1] = 1;
            trigger_teeth[2] = 5;
            trigger_teeth[3] = 9;


Then simply recompile, and you should be golden. Me, I'd just change the wiring until your issue comes around on the to-do list..

[jsmcortina]

If everyone is agreed that this change needs making, it will be done in the next beta firmware release.

James

[opel]

If everyone is agreed that this change needs making, it will be done in the next beta firmware release.

James

Thanks James,

Any chance you could send me a test firmware?

Thanks

[opel]

If you can run the MS3 1.0.3 firmware, you can fix this yourself. Download the source, open "ms3_ign_wheel.c" in a text edittor, Find this section:

Code: Select all


            trigger_teeth[1] = 9;
            trigger_teeth[2] = 13;
            trigger_teeth[3] = 1;


James, feel free to correct me if I'm interpreting this wrong, but I think you need to change this section to:

Code: Select all

            trigger_teeth[0] = 13
            trigger_teeth[1] = 1;
            trigger_teeth[2] = 5;
            trigger_teeth[3] = 9;


Then simply recompile, and you should be golden. Me, I'd just change the wiring until your issue comes around on the to-do list..

Thanks! I will give this a shot

[SymTech Laboratories]

If everyone is agreed that this change needs making, it will be done in the next beta firmware release.

Per our PM's, this does seem like a change that needs to be made. Thanks!

[juansh2385]

Hey James could this also affect the sequential injection order for this code?

Please correct me if I am wrong but I notice that ms2 have the same code in the 420a wheel decoder does this mean that ms2 is also affected by this?

Juan

[jsmcortina]

As MS2 is using the same code then the result is the same yes.

James

[juansh2385]

edit* (it sounded as if was saying that the code is the reason when is not )

I am running sequential injection and waste spark ign so its harder for me to notice if the injection is out of phase too, but I am assuming that if the both injection and ignition are affected by this. I am going to scope my car to see if in my car injection 1 is out of phase and report back.

Thanks.

Juan

[racingmini_mtl]

The injection will have the same phase as the ignition. However, having an out of phase injection will not melt a piston but at worse would mean a rougher running engine.

Jean

[juansh2385]

Jean I also agree with you that the melted piston is not fault of the code it is probably a bad in a injector or something like that but i am sure that bad phase does not help. Any ways thanks for the help as always. I will report back if I can confirm also that my car is out of phase.

Juan

[opel]

Any chance for a test firmware soon? I want to finalize my wiring, need to get to the racetrack someday. (please )

[turbodoug]

I was able to duplicate this issue as well. Good find!

Both spark and fuel were out of phase.

This was fixed in the most recent code version "pre1.1beta22". I've tested this code on the bench as well as on the car and the spark/fuel phase is now correct.

[opel]

OK - it looks right on the scope, I will wire up my car and see how it runs. Thank you for the fix!!!

[opel]

It works! Car is up and running and idle is smoother than ever!

[juansh2385]

Great to know James is the fix that you implemented the same as the one that was presented here? I want to try it in my ms2.

Juan