Bringing TBI and Multi Port Fuel Injection to a New Level.     EFI Conversions and Tuning! Seattle to Portland! E-mail Tuning Consultant!
Results 1 to 7 of 7

Thread: 16183977 PCM Information $EC Turbo Diesel

  1. #1
    EFI GearHead ! EagleMark's Avatar
    Join Date
    Feb 2011
    Location
    North Idaho
    Age
    57
    Posts
    10,477

    16183977 PCM Information $EC Turbo Diesel

    16183977 PCM Information $EC used in 6.5L Turbo Diesel engines around 1994

    Thanks to daleulan for bins and dissasembly information to start this thread!

    **Work In Progress**

    1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
    1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
    -= =-

  2. #2
    EFI GearHead ! EagleMark's Avatar
    Join Date
    Feb 2011
    Location
    North Idaho
    Age
    57
    Posts
    10,477

    16183977 bin and disassembly of $EC

    16183977 bin and disassembly of $EC
    Attached Files Attached Files

    1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
    1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
    -= =-

  3. #3
    EFI GearHead ! EagleMark's Avatar
    Join Date
    Feb 2011
    Location
    North Idaho
    Age
    57
    Posts
    10,477

    TunerPro Definition files for 16183977 $EC

    TunerPro Definition files for 16183977 $EC

    *Removed as they appeared to be copied from Copyright material. *

    1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
    1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
    -= =-

  4. #4
    EFI GearHead ! EagleMark's Avatar
    Join Date
    Feb 2011
    Location
    North Idaho
    Age
    57
    Posts
    10,477

    TunerPro ADS ADX Definition files for 16183977 $EC

    TunerPro ADS ADX Definition files for 16183977 $EC

    None have been deleloped at this time. Here is the information and ALDL.ds files needed.
    DATA STREAM A225
    PCME DIESEL
    PCM USAGE:
    L49 PFI 6.5L VIN = P 1994 C,K,G 4L60E/MANUAL TRANS.
    L56 PFI 6.5L TURBO VIN = S 1994 C,K
    L65 PFI 6.5L TURBO VIN = F 1994 C,K,P MANUAL TRAN.
    * L49 PFI 6.5L VIN = P 1995 C,K,G 4L60E/MANUAL TRANS.
    * L56 PFI 6.5L TURBO VIN = S 1995 C,K 4L80E
    * L65 PFI 6.5L TURBO VIN = F 1995 C,K,P MANUAL TRANS.

    DATA STREAM A226
    4L80E DIESEL TRANS.
    PCME USAGE:
    L49 PFI 6.5L VIN = P 1994 C,K,G 4L60E/MANUAL TRANS.
    L56 PFI 6.5L TURBO VIN = S 1994 C,K
    * L49 PFI 6.5L VIN = P 1995 C,K,G 4L60E/MANUAL TRANS.
    * L56 PFI 6.5L TURBO VIN = S 1995 C,K 4L80E
    Attached Files Attached Files

    1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
    1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
    -= =-

  5. #5
    Super Moderator
    Join Date
    Mar 2011
    Location
    Camden, MI
    Age
    28
    Posts
    3,021
    so..... information explosion here:

    http://www.10000cows.com/stanadyne-ds4.htm

    Stanadyne DS4 and GM PCM.... yea, quite a piece
    of work.


    The Stanadyne DS4 injection pump has a few issues...
    obviously. So does the software in the PCM. Let's start with my first rant... a
    fair number of people bitch at the EPA and blame them for all of the automaker's
    woes and all of this emission control and 'other crap we don't need'. Well, that
    would be acceptable, perhaps, if you had a life expectancy of, oh, twenty five
    years or maybe thirty, thanks to automobile pollution. Automotive emission
    controls is one of the more important inventions in automobiles. Well, maybe
    not. Perhaps we would be all driving electrically-operated vehicles instead.
    Emission controls really do not add that much cost to a vehicle. Safety
    equipment such as air bags, crush zones, and crash testing all add lots of cost
    and time and complexity. We complain about those, too, unless we're on the
    receiving end of that safety equipment - if it saves your life. The radios and
    DVD players, now they add cost and complexity. All of the gadgets like
    windshield wipers that run automagically in the rain, or windows that open so
    you can close the door, then close once you're done, that's added (and probably
    unnecessary) complexity. Electronic engine management is not that expensive, and
    even many of the developing countries (India, China) have been running
    electronic diesel controls for a few years now - it can't cost that much. Delphi
    is building common-rail diesel injection systems for LAWNMOWER ENGINES! That
    can't be terribly expensive!

    Why does the 6.5L have so many problems? People tend to
    blame electronics (or the EPA) but there has not been a highway truck built
    since the late 1980's without electronic engine management. The well-loved
    Detroit series 40, 50, and 60 are all electronically controlled - the engines
    were designed that way. Even the last V92 family received electronic fuel
    injection. The Cat 3406, Cummins ISX, (and ISL, ISC, and
    ISB), Powerstroke, and DT466E - these are engines that last a million miles
    between rebuilds, and all electronically controlled. You can breathe the air
    thanks to all of this technology. You want to see what happens when you don't do
    this? Go visit India and China and Russia. Visit a bus barn in Hungary or Brazil
    full of Rabas or 'Old Smoky' Mercedes OM352. So what went wrong? Let's look at
    what we are working with....

    The 1994-1995 6.5L TD ECM consists of a fairly low-tech set
    of chips. The main processor is a 68HC11F1 running with a 12.59 MHz crystal.
    There's about 48k of code and calibration space available. A Delphi IOR chip
    supplies 240 bytes of RAM and also some I/O ports and four PWM channels. A
    configurable timer chip is used to process pulses from the diesel pump's optical
    encoder and also the CKP signal. Not a big problem except that the people
    writing the software screwed up a bit. There are a few bugs in the software. The
    ones I have found include:



    • The software filter used to prevent ECTS-based tables from
      chattering with sensor noise is not functional. There is supposed to be a
      deadband of 2 degrees C, however, that deadband comparison is screwed up because
      of a missing # sign in a CMPB instruction in the source code. Something of note
      is that the OBD-II version of the software does not correct this.
    • A flag fetch from calibration does not get the correct
      mask. The problem here is a missing # sign in a BIT instruction in the source
      code. There are a couple of cases of this. One of them may actually cause a fuel
      dropout in the case of certain unrelated DTC's setting. It looks like that part
      of the code was rewritten for the OBD-II version.
    • The SCI interrupt is not equipped to be interrupted by the
      CKP, CMP, VSS, or OSS interrupts. That would be fine if the interrupt just
      stored the appropriate data and called the main program loop to actually form an
      SCI message. But it doesn't. So what happens is you miss interrupts if you have
      a scan tool connected. The correct solution would have been to disable the 160
      Hz interrupt, disable the SCI interrupt, re-enable global interrupts, format the
      outgoing data stream, disable global interrupts, re-enable the SCI interrupt,
      re-enable the 160 Hz interrupt, then return from SCI interrupt. The OBD-II
      version checks during long interrupt-disabled conditions now so this is not a
      problem any more.
    • The subroutine used to calculate the desired EGR pressure
      is called twice in a row. This was corrected in the OBD-II version of the
      code.
    • In several spots, a double-precision arithmetic operation
      (subd, addd) only loads half of the input, leaving the other register containing
      some random stuff.
    • In several spots, engine speed (and sometimes other things
      - but engine speed happens multiple times) is calculated, then is just thrown
      away.


    Other than that, the ECM probably will do its job,
    more-or-less all of the time. Automotive ECM's have been shown to be rather
    reliable and there's no particular reason to think this one has a big
    problem.

    The pump driver module has a reputation of blowing up. Yea,
    probably it deserves it. To start with, it appears to use a couple of huge
    bipolar transistors configured as a high-side switch, and also as a linear
    current regulator. I don't think I would do it that way. Using MOSFETs to switch
    the solenoid valve along with a high-speed PWM current regulator would be a much
    better solution IMHO. The Cummins ISC system, which uses a similar pump control
    solenoid, uses PWM control. The current trace is a straightforward linear 12A
    current limit. That would make a peak power dissipation (not including clamping)
    of around 100 watts. This might be
    interesting for someone who is circuit-minded.

    The optical sensor has issues. It is bathed in diesel fuel,
    and is at the mercy of whatever is in there. Air bubbles? Funny thing is that
    Bosch has a VP44 pump with an optical encoder, as well, and it does not have a
    bad reputation. Does an 8-cylinder VP44 pump exist? Perhaps a good retrofit kit
    would be a VP44 and a new ECM.

    The diesel pump. It is a solenoid-controlled rotary pump.
    There are several ways of modulating fuel and timing in an electronically
    controlled diesel pump. They are...


    • Sliding rotor (EPIC). This limits plunger travel
      mechanically, using hydraulic pressure. The ECM controls the pressure using a
      pair of solenoid valves.
    • Mechanical start-of-injection, solenoid spill (Lucas,
      Stanadyne DS4 in pump-spill mode). Start-of-injection is mechanical so the
      stresses on the pump are only huge. End-of-injection has some pretty substantial
      forces associated with it.
    • In-line sleeve pump with prestroke control. Injection
      quantity is controlled via fuel rack, start-of-injection is controlled by timing
      rack. Based on the old Bosch inline pump, used on John Deere tractors, and a
      Zexel version is used on some older Isuzu trucks.
    • Control collar (Bosch VP37). This controls fuel quantity
      usually via fuel throttling (cavitation of the pump) or stroke control. Timing
      is controlled via servo-controlled timing piston, similar to mechanical pumps.
      Injection timing must be measured with an electromagnetic injector.
    • Solenoid SOI, solenoid spill (Bosch VP30, VP44, Stanadyne
      DS4 in spill-pump-spill mode). Most flexible until we get to common rail
      (Duramax).
    • Brute Force Electronic Unit Injector,
      spill-pump-spill.
    • Diesel timed injector. Uses liquid plunger made with diesel
      fuel to vary plunger length and injection timing, Cummins ISX.
    • Common rail or distributor brute-force injection. Uses a
      solenoid valve as in a straightforward metering system (very much like a
      gasoline fuel injector). Duramax, Cummins ISC, Smart ForTwo CDI.


    The design requirements for solenoid spill are substantial.
    Stanadyne didn't get one or two of them right. Things that they might have got
    not-quite-right:


    • Slope of cam too aggressive (desired pressure or pumping
      rate too high) for materials.
    • Pump cavitation is causing an issue.
    • Resonances in the pump causing multiplication of forces
      beyond expected values.
    • The pump appears to rely on centrifugal force to pull the
      plungers out - the whole case seems to be pressurized about equally. I think
      that is a function of the fill/spill solenoid arrangement. If the inlet of the
      injection pump is at a significantly higher pressure than the rest of the pump,
      more solid operation should be assured. I'm not 100% sure on this but the
      pumping plunger assembly looks a bit suspect to me. I'd probably want to get a
      dead pump and disassemble it to figure out if this would be an issue or not,
      perhaps my understanding of the internal plumbing and case pressure control is
      flawed.


    16183977 ECM (1994-1995)


    Here is a photo of the guts of the 1994 to 1995 ECM. I have
    never seen a photo of this ECM's guts, so I took the liberty of making this one.
    I think a lot of people get lost from here down, but what follows is something
    that any ECM hacker probably could figure out with a meter and the ECM in front
    of them.



    Parts on the board of note:


    • 16055199 = voltage regulator
    • 16166240 = quad driver module with diagnostics
    • 16034993 = stepper motor driver
    • 16064606 = serial output driver
    • 16084523 = SO-20 VR sensor amplifier for transmission input
      shaft speed
    • 16158016 = 74HC4067 analogue mux
    • 45555 = LM339 comparator
    • 48025 = SO-14 quad NAND gate, 74HC00
    • 27375 = SO-14 dual AND/NOR gate, 74HC51
    • 50610 = LM2904 dual op-amp
    • 49226 = LM393 dual comparator
    • 27377 = LM2902 quad op-amp
    • 66285 = PLCC-68, Delphi IOR, mapped at $1400
    • 16156598 = PLCC-68, MC68HC11F1, 3MHz rating
    • 16180988 = PLCC-68, timer I/O module
    • EPROM carrier, T+B 'BLUE' carrier


    I/O Assignments:


    • AN0 = APP
    • AN1 = APP
    • AN2 = Transmission force current monitor
    • AN3 = APP
    • AN4 = battery voltage
    • AN5 = boost pressure, via Sallen-Key filter
    • AN6 = analogue mux
    • AN7 = EGR/baro pressure, via Sallen-Key filter
    • PAI = 4004 pulse per mile VSS input
    • TIC1 = Pin C15, VSS
    • TIC2 = Pin C12, transmission input shaft speed, through
      84523 buffer
    • TIC3 = 8X CMP signal (low-res pump encoder signal). Also
      fed into 16180988 IC.
    • TIC4 = 4X CKP signal (from engine CKP). Also fed into
      16180988 IC.
    • TOC4 = backup injector pulse width generation
    • TOC3 = I/O pin disables injector from TIO chip, timer
      channel used for 160 Hz task scheduler
    • TOC2 = TCC PWM generation
    • PD5 = powerdown to power supply IC
    • PG0 = ODM2-7
    • PG1 = ITS-9 (ITS phase)
    • PG2 = ITS-6 (ITS phase)
    • PG3 = SCI transceiver control


    AN Mux:


    • MUX0 = pin B8, glow plug voltage monitor
    • MUX1 = pin B11, fuel temperature signal
    • MUX2 = pin A12, diagnostic switch input
    • MUX3 = Pin C8, ECTS voltage
    • MUX4 = pin B9, spare, 220k pulldown
    • MUX5 = pump calibration
    • MUX6 = QDM1-14 fault input
    • MUX7 = pin C13, glow plug relay supply voltage
    • MUX8 = QDM2-14 fault input
    • MUX9 = pin B4, A/C request
    • MUX10 = pin B12, intake air temperature
    • MUX11 = pin D10, optical sensor 5V power supply
    • MUX12 = Pin B5, unused, 20V range, 3k pullup to key
      power
    • MUX13 = pin C9, Transmission temperature sensor
    • MUX14 = APP 2 sensor 5V power supply
    • MUX15 = unused, grounded on input mux


    IOR:


    • 1400.7 = PCS Low Drive
    • 1400.6 = TCC on/off output (4L60E)
    • 1400.5 = shift solenoid
    • 1400.4 = shift solenoid
    • 1400.3 = EGR vent valve
    • 1400.2 = Service Throttle Lamp
    • 1400.1 = ITS Enable
    • 1400.0 = Glow plug relay enable
    • 1402.7 = AMUX3
    • 1402.6 = AMUX2
    • 1402.5 = AMUX1
    • 1402.4 = AMUX0
    • 1402.3 = Pin E2 - 4WD axle switch
    • 1402.2 = Pin E3 - Performance shift mode switch
    • 1402.1 = Pin E4 - Manual shift mode switch
    • 1402.0 = Pin F3 - cruise on/off
    • 1404.7 = Pin F11 - cruise resume/accel
    • 1404.6 = Pin F15 - cruise set/coast
    • 1404.5 = Pin E10 - PRNDL B
    • 1404.4 = Pin E9 - PRNDL C
    • 1404.3 = Pin E8 - PRNDL A
    • 1404.2 = Pin F5 - TCC Brake Switch
    • 1404.1 = Pin A6 - Brake Switch
    • 1404.0 = Pin A6 - PTO request
    • 1407.3 = MIL
    • 1407.2 = Read pump trim resistor enable
    • 1407.1 = Pin C9 Transmission Temp Pullup Select
    • 1407.0 = Pin C8 IATS Pullup Select
    • 1408 (PWM) = PCS current control
    • 140A (PWM) = Boost modulator control
    • 140C (PWM) = spare, not sure what it is used for yet.
      Probably the 3-2 shift solenoid, 4L60E.
    • 140E (PWM) = EGR frequency


    TIO:


    • 1AFA.1 = ODM chip select to retrieve diagnostic
      status
    • 1AFA.2 = ODM chip select to retrieve diagnostic
      status
    • 1872 = closure time response
    • 187C = timing delay counter
    • 187E = fuel quantity counter
    • 1880 = split pulse delay counter
    • 1882 = pilot quantity counter (first pulse)


    16193570 ECM (1996+)


    Parts on the OBD-2 version of the board
    (16216588):


    • 16055199 = voltage regulator
    • 16166240 = quad driver module with diagnostics
    • 16034993 = stepper motor driver
    • 20686 = SAE J1850 transceiver and controller
    • 66285 = PLCC-68, Delphi IOR, mapped at $1400
    • 16202476 = PLCC-68, MC68HC11F1
    • 39985 = PLCC-68, timer I/O module
    • 16183784 = AN28F010 128k by 8 flash memory module
    • 16206550 = ?


    I/O Assignments:


    • AN0 = APP
    • AN1 = APP
    • AN2 = Transmission force current monitor
    • AN3 = APP
    • AN4 = battery voltage
    • AN5 = boost pressure, via Sallen-Key filter
    • AN6 = analogue mux
    • AN7 = EGR/baro pressure, via Sallen-Key filter
    • PAI = 4004 pulse per mile VSS input
    • TIC1 = Pin C15, VSS
    • TIC2 = Pin C12, transmission input shaft speed, through
      84523 buffer
    • TIC3 = 8X CMP signal (low-res pump encoder signal). Also
      fed into 16180988 IC.
    • TIC4 = 4X CKP signal (from engine CKP). Also fed into
      16180988 IC.
    • TOC4 = backup injector pulse width generation
    • TOC3 = I/O pin disables injector from TIO chip, timer
      channel used for 160 Hz task scheduler
    • TOC2 = TCC PWM generation
    • PD5 = powerdown to power supply IC
    • PG0 = ODM2-7
    • PG1 = ITS-9 (ITS phase)
    • PG2 = ITS-6 (ITS phase)
    • PG3 = Firmware bank selection


    AN Mux:




    • MUX0 = pin B8, glow plug voltage monitor
    • MUX1 = pin B11, fuel temperature signal
    • MUX2 = pin A12, diagnostic switch input
    • MUX3 = Pin C8, ECTS voltage
    • MUX4 = pin B9, spare, 220k pulldown
    • MUX5 = pump calibration
    • MUX6 = QDM1-14 fault input
    • MUX7 = pin C13, glow plug relay supply voltage
    • MUX8 = QDM2-14 fault input
    • MUX9 = pin B4, A/C request
    • MUX10 = pin B12, intake air temperature
    • MUX11 = pin D10, optical sensor 5V power supply
    • MUX12 = Pin B5, unused, 20V range, 3k pullup to key
      power
    • MUX13 = pin C9, Transmission temperature sensor
    • MUX14 = APP 2 sensor 5V power supply
    • MUX15 = Flash memory Vpp monitor


    IOR:


    • 1800.7 = PCS Low Drive
    • 1800.6 = TCC on/off output (4L60E)
    • 1800.5 = shift solenoid
    • 1800.4 = shift solenoid
    • 1800.3 = EGR vent valve
    • 1800.2 = Service Throttle Lamp
    • 1800.1 = ITS Enable
    • 1800.0 = Glow plug relay enable
    • 1802.7 = AMUX3
    • 1802.6 = AMUX2
    • 1802.5 = AMUX1
    • 1802.4 = AMUX0
    • 1802.3 = Pin E2 - 4WD axle switch
    • 1802.2 = Pin E3 - Performance shift mode switch
    • 1802.1 = Pin E4 - Manual shift mode switch
    • 1802.0 = Pin F3 - cruise on/off
    • 1804.7 = Pin F11 - cruise resume/accel
    • 1804.6 = Pin F15 - cruise set/coast
    • 1804.5 = Pin E10 - PRNDL B
    • 1804.4 = Pin E9 - PRNDL C
    • 1804.3 = Pin E8 - PRNDL A
    • 1804.2 = Pin F5 - TCC Brake Switch
    • 1804.1 = Pin A6 - Brake Switch
    • 1804.0 = Pin A6 - PTO request
    • 1807.3 = MIL
    • 1807.2 = Read pump trim resistor enable
    • 1807.1 = Pin C9 Transmission Temp Pullup Select
    • 1807.0 = Pin C8 IATS Pullup Select
    • 1808 (PWM) = PCS current control
    • 180A (PWM) = Boost modulator control
    • 180C (PWM) = spare, not sure what it is used for yet.
      Probably the 3-2 shift solenoid, 4L60E.
    • 180E (PWM) = EGR frequency


    TIO:




    • 16FA.1 = ODM chip select to retrieve diagnostic
      status
    • 16FA.2 = ODM chip select to retrieve diagnostic
      status
    • 1472 = closure time response
    • 147C = timing delay counter
    • 147E = fuel quantity counter
    • 1480 = split pulse delay counter
    • 1482 = pilot quantity counter (first pulse)
    • 140C = MAF time-since-last-pulse (pin C3 of the 32 pin
      BROWN connector, NOT pin E1 (or sometimes called pin C1 of connector C3). THIS
      IS WRONG in some service schematics!
    • 140A = MAF pulse counter




    This is a 68HC11 processor which should be very similar to
    that used in the OBD-I version. It is a bit unusual (to my mind) to use a 68HC11
    on the OBD-II ECM when pretty much all of the OBD-II petrol ECM's went to
    68332's. I guess Ford pushed the EEC-V (8065, a 8096 variant) just into the
    2000's before going over to the PowerPC's so why not, I guess. Just to be a pain
    in the arse, the flash memory has some of its address lines swapped around.
    There's space for two 32k memory pages (bank swapped using pin PG3) and one 24k
    non-banked page shared between calibration and common (non-banked) code.
    Communication is via SAE J1850 instead of SCI.

    The Pump (and its control algorithms) - both OBD-I and OBD-II


    How does the pump actually work, and how is it controlled?
    It's not really that hard. I could write this sort of code in my
    sleep.

    The optical sensor has a 64 pulse per cylinder and a 1 pulse
    per cylinder track. The 1 pulse per cylinder track fires at the pump reference
    location which is 22.2 engine crank degrees before the start of injection. This
    pulse is nominally timed at 25.66 crank degrees before TDC of the engine - this
    is performed by doing the TDC reference offset procedure. This procedure assumes
    that the timing of the engine CKP is spot-on, and the pump is out. This also
    means that the most retarded SOI that the pump is normally capable of is 3.5
    degrees of advance. Since the most retarded idle timing I have seen is about 6
    crank degrees, that gives sufficient margin to accept the +/- 2 degrees allowed
    in the TDC offset procedure. Note that these timing values only count at idle.
    Due to variations in how a pump works, the actual timing of injection will vary.
    Note that in theory, the TDC offset procedure should not even be necessary. The
    TDC information is constantly there and could be used to learn the offset during
    normal operation.

    When looking at a scan tool, there are several values
    displayed. The value 'Actual Injection Pump Timing' which shows about 28 crank
    degrees at idle, is the engine clock count (in engine degrees) between the
    injection pump reference pulse and the TDC reference pulse, corrected for TDC
    offset. The measured injection timing (around 6 degrees at idle) is then taken
    from the actual pump timing value, then subtract out the 22.2 crank degree
    reference-to-SOI offset. The desired injection pump timing simply comes from a
    summation of three lookup tables - base injection timing, ECTS adder, barometric
    adder, and IATS adder. That's it - it's actually pretty simple.

    With these two numbers, the ITS stepper motor is moved
    back-and-forth, trying to maintain the measured injection timing at the actual
    injection timing. If these values vary more than a couple of degrees from each
    other, a DTC will set.

    The injection metering pulse width (which is in crank
    degrees, and NOT in milliseconds), comes basically from the pump mapping tables.
    It is the summation of two pump mapping tables, which contains the number of
    crank degrees from the pump reference to EOI (end-of-injection). One mapping
    table is the base delivery vs. pump rotation. The other includes pumping
    efficiencies and is dependant on pump speed. The base pump map table is crank
    degrees from RPM and desired fuel quantity (in cubic millimetres). The pump
    resistor calibration causes a small shift in the pump mapping tables - maybe by
    one or two crank degrees. The pumping cycle at idle is set up so that the
    metering valve closes at the pump reference location. It actually accomplishes
    this by generating a time delay of 83.58 crank degrees from the previous pump
    reference location. The 6.42 crank degrees to make it 90 is calculated as the
    measured injection opening delay of about 1.7 milliseconds at idle. The
    'injector pulse width' shown on the scan tool is actually the injector response
    time. It is measured by monitoring the dip in metering valve solenoid current as
    the armature moves. Many other diesel engines using 12V injection actuation
    (Detroit Diesel, Cummins CAP system) do this measurement so it's not that
    unusual.

    If you like graphics, here is a timing diagram.

    Optionally, the metering valve can be closed later in the
    pumping cycle - about 12 or 15 crank degrees - without affecting fuel metering
    significantly. This is because the normal spill valve closure time is designed
    to be in a flat spot of the camring so that the normal variance in valve closing
    time does not affect fuel timing. In a backup mode, valve closing may be used to
    control fuel timing, but normally the engine is running in a highly derated
    mode.

    The ECM supports split injection. I have worked on the
    Cummins ISC which also supported split injection. It really does help warmup.
    But the calibration file doesn't seem to use split injection, and I'm wondering
    if the cold warmup would be more pleasant with it. I do not know the
    thermodynamic properties of split injections in a prechamber diesel. On a direct
    injection engine, the pilot injection really does make the engine much more
    pleasant. It's certainly a lot quieter and smoother, anyways. The firmware in
    this ECM does not handle split injection very well - it 'supports' it but not
    well. For one, the firmware does not compensate for spilled fuel. The other is
    that the algorithm splits after the pump maps which does not account for the
    dead zone in metering. I don't think anyone gave split injection even an attempt
    given that the software is a bit goofy.

    A few of the other functions are pretty obvious. EGR is simply a servo loop
    that sets the MAP sensor to the desired pressure value. During highway operation
    the EGR system is turned off. It is only used in city driving. Boost pressure
    control is also pretty obvious. It works exactly the same way as the EGR system.
    The transmission uses pretty much the same code and logic as the gasoline
    versions. For some drivetrain applications, engine torque can be reduced based
    on torque converter slip (torque multiplication).

    Back to the ECM hardware (and a bit of software).... Counter
    Logic:


    • Engine clock counts is in units of 8192 / 720 crank
      degrees
    • Injection Timing Counter: Start at pump reference, stop at
      TDC reference, count in engine clock counts
    • Injection Response Counter: Start at first injector
      energize, stop at closure detect, count in E/64 (fixed speed clock)
    • Injection Delay Counter: Start at pump reference, stop and
      energize injector when counter reaches zero, count in engine clock counts.
      Normally around 75-90 crank degrees of delay.
    • Injection Pilot/Initial Quantity Counter: start at injector
      energize, stop and turn off injector when counter reaches zero, count in engine
      clock counts. Normally between 20 and 35 crank degrees of delay.
    • Injection Pilot to Main/Split Delay Counter: Start at main
      quantity counter expire, stop and turn on injector when counter reaches zero,
      count in engine clock counts. Not used in the 6.5L.
    • Injection Split/Main Quantity Counter: start at pilot delay
      counter expire, stop and turn off injector when counter reaches zero, count in
      engine clock counts. Not used in the 6.5L.


    Note that in 'backup mode' - where the high-res pump signal
    is lost, the 68HC11 can generate injection timing signals based on the
    low-resolution inputs, however, that is not the preferred mode that the ECM
    wants to run in. In this case, the desired injector delivery is divided by
    engine speed to generate a pulse width. At this point, the pulse is then
    generated using the free-running TCNT system on the 68HC11.

    How do you get more power? Carefully. If the rest of the
    engine will take it, you need to calibrate the injection pump table to make full
    use of the pump. The total pumping range of the DS4 is about 80 or so cubic
    millimetres of fuel - even more than the mechanical DB pump. However, adding
    boost, lowering intake air temperature (via an intercooler), and careful mapping
    of injection timing is the 'right' way to do it. Injection timing should be
    mapped and adjusted for a careful balance of exhaust temperatures and NOx
    formation. High exhaust temperatures are obviously not good. But neither is high
    NOx - not only for the emissions aspect (you may not care about that), but also
    for engine life (and you probably do care about that). Excessive NOx indicates
    excessive cylinder pressures - pressures above the design rating of the engine.
    Diesel engines don't really knock at high power, they just blow up, leaving you
    on the side of the road with a lot of hot, oily pieces hanging out. Well, maybe
    not that often, but keep in mind that there are plenty of TSB's for detecting
    engine damage due to 'chipping'. The engine manufacturer knows the tolerance of
    their engine production and how far they can push *all* of that engine model.
    Yours may take more, or maybe not.

    Advancing the timing and cranking up the fuel is a great way
    to make a lot of smoke (ie. waste a lot of fuel), make only a little bit more
    power, and shorten the life of your engine. Add an air-to-air intercooler to
    your 6.5L diesel engine and it will be a lot happier. You will get more power,
    lower exhaust emissions (not that most people care about that - it's a side
    benefit), and longer engine life. I'm not going to go plugging the EGR system,
    at least not on my truck. The engine is timed and calibrated assuming the EGR
    system is working, and I have a bit of a concern for the environment. In
    particular, what the EGR system goes after - the nitrogen oxides that cause the
    brown haze.

    I'm aware of some quotes and criticisms of this writeup,
    especially regarding EGR removal and that sort of thing. I can't claim that the
    6.5L will blow up or melt or whatever if you pull off your EGR system - probably
    it won't. EGR lowers the PEAK combustion pressure while broadening its shape -
    slowing the burn. In order to optimize power and fuel efficiency while reducing
    NOx, the engine calibrator normally will compromise between EGR and timing to
    give an acceptable ratio of PM (particulates) and NOx. By increasing EGR rate
    you slow down the burn and to not drop power or efficiency, you have to advance
    the injection timing a bit. Gasoline engines do this, as well. But in a gasoline
    engine knock is occasionally expected so the knock detection system will prevent
    engine damage. Back to NOx/PM. In this art compromise, you can increase PM and
    lower NOx to meet the emissions requirements, or you can raise NOx and lower PM.
    Lowering NOx may raise exhaust temperatures and drop efficiency so you have
    those two items to worry about, too. Whether or not 'a bit' is an issue depends
    on your design margins. I have seen engines blow up with just small things wrong
    with the controller - apparently they had little margin for error. I have seen
    natural gas engines that would melt pistons without EGR - engine knocking. I'm
    not making that up, it's well published. A certain well-known natural gas engine
    needed to have its redline lowered from 2400 to 2200 - well below the mechanical
    limits of the engine. That was because they could not control EGR tightly enough
    at full power conditions to prevent knocking - that's right, EGR at full power.
    That engine had little margin and needed EGR to control engine knock and exhaust
    temperatures even at full-tilt operation. The 6.5L may have lots of margin and
    may 'take it'. I would guess that the injection timing of the non-EGR 6.5L
    engines is less advanced than the EGR-equipped versions.

    The other thing I'm aware of are some posts saying that this
    emissions stuff is government communist crap since cows emit more than engines.
    But cows only emit substantial quantities of CO2 and CH4, both fairly harmless.
    Perhaps greenhouse contributors but I'm not too worried about that. Diesel
    engines without aftertreatment spew out a toxic concoction of nitric oxide (acid
    rain, brown smog, respiratory problems, rapid tarnishing of copper pub tables
    and silverware), carbon monoxide (competes for oxygen transport in animals - it
    suffocates you), unburned hydrocarbons which include some nasty circular
    benzene-ish compounds (known carcinogens), and particulate matter (also
    carcinogenic and respiratory irritants). Perhaps the tailpipe should discharge
    right into the cab of the vehicle so the operator of the vehicle can enjoy their
    exhaust as much as the people behind them.

    My background, by the way, is an engine management designer
    and calibrator, and I've blown up a bit of stuff here and there. Including
    $10,000 prototype catalytic converters, a few engines, and even a
    dyno.[/quote]
    Attached Files Attached Files
    1995 Chevrolet Monte Carlo LS 3100 + 4T60E


  6. #6
    Super Moderator
    Join Date
    Mar 2011
    Location
    Camden, MI
    Age
    28
    Posts
    3,021
    newellshk pointed out to me that there has never been an ADS or ADX uploaded for these PCMs, an ADS has been in my archive since 2009, I guess now is as good as time as any to post it.
    Attached Files Attached Files
    1995 Chevrolet Monte Carlo LS 3100 + 4T60E


  7. #7
    Administrator
    Join Date
    May 2011
    Location
    Lakes Region, NH
    Age
    47
    Posts
    2,755
    XDF and partial disassembly contributed by newellshk.
    Attached Files Attached Files

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •