How to Datalog with a Chipped OBD1 P28 ECU

Complete guide to connecting your ECU, uploading tunes, recording datalogs, and troubleshooting connection issues.

Datalogging is one of the most important tools when tuning a modified Honda or Acura engine. It allows us to monitor actual engine information such as RPM, coolant temperature, throttle position, air/fuel ratio (AFR), and other ECU parameters.

At DGTune, we use this information to identify problems, evaluate engine performance, and make more accurate tuning adjustments.

This guide covers chipped Honda OBD1 ECUs using:

  • USB datalogging cable only (no emulator installed).

  • Moates Demon V1 (original Demon).

  • Moates Demon V2 (Demon II).

  • Snake Emulator (Snake OBD1 EMU / Snakemu, depending on model).

Although these setups share similar datalogging procedures, their connection settings and tuning capabilities are different.

Before You Begin: ECU Hardware Requirements

Your chipped ECU must be properly prepared for datalogging.

For conventional chipped Honda OBD1 ECUs using a CN2 datalogging connection:

  1. J12 jumper must be completely removed. This is essential for proper datalogging communication on applicable ECU boards.

  2. CN2 datalogging header must be installed. This provides the connection for compatible datalogging equipment.

  3. Your ECU must have compatible datalogging software and hardware. A chipped ECU with a removable tuning chip does not automatically support datalogging.

Note: J12 applies to many USDM Honda OBD1 ECUs. Certain JDM ECU boards use a different jumper location, such as J4. Verify your ECU's specific board configuration before making modifications.

If your ECU has not been properly prepared, HTS may be unable to establish communication, regardless of which settings you select.

Get your ECU serviced by DGTune Today: Click here!

Step 1: Download and Install Honda Tuning Suite

Download the latest available version of Honda Tuning Suite.

Download Honda Tuning Suite (HTS)

We recommend using HTS 2.22 Snake Tuning Edition or a newer compatible release if one becomes available.

Once installed:

  1. Connect your laptop to the ECU using your USB datalogging cable or emulator.

  2. Open Honda Tuning Suite.

  3. Go to File → Settings → Emulator/Datalogging.

  4. Configure HTS according to the hardware installed in your ECU.

A. Standard Chipped ECU — USB Datalogging Cable Only (No Emulator)

If your ECU uses a removable tuning chip and a USB datalogging cable connected to CN2, but does not have an emulator installed, you will usually need to select:

Emulator → Ostrich

Even though your ECU does not have a physical Ostrich emulator, this is commonly the setting used in HTS for cable-only datalogging configurations.

Next:

  1. Select the correct COM port assigned to your USB datalogging cable.

  2. Make sure your USB drivers are installed correctly.

  3. Save your settings.

  4. Connect to the ECU using the datalogging connection in HTS.

If you cannot connect, try another available COM port.

IMPORTANT — Open Your Tune File!

Even when using a USB datalogging cable without an emulator, you should still open the original tune file provided by DGTune.

Go to:

File → Open → Select your DGTune tune file

Opening the tune allows HTS to display the fuel and ignition maps associated with your setup.

As the engine runs and you record data, HTS can show which areas of the tune are being accessed based on RPM, engine load, and other parameters.

This makes datalogging much more useful because you can see where the engine is operating within the tune instead of viewing only sensor readings.

Opening the tune file DOES NOT upload or change anything in your ECU.

With a cable-only setup:

  • You CAN view live engine data.

  • You CAN record and save datalogs.

  • You CAN view the datalog information in relation to the opened tune file.

  • You CANNOT upload, modify, or overwrite the tune stored on the removable ECU chip.

The file opened in HTS should match the tune currently installed on the ECU for accurate table tracking.

Any tune adjustments will require a newly programmed chip or an upgrade to compatible emulator hardware.

B. Moates Demon V1 and Demon V2

There are two versions of the Moates Demon emulator:

Moates Demon V1 (Original Demon)

The original Demon supports realtime ROM emulation and ECU datalogging. It uses battery-backed memory and can be installed in a range of compatible USDM and JDM Honda OBD1 ECUs.

Moates Demon V2 (Demon II)

The newer Demon II also supports realtime tuning and datalogging, but uses updated hardware and nonvolatile ROM storage. It was designed primarily for compatible USDM Honda OBD1 ECUs.

Both Demon V1 and Demon V2 can be used with Honda Tuning Suite when properly configured.

For either version:

  1. Open File → Settings → Emulator/Datalogging.

  2. Under Emulator, select Moates Demon.

  3. Select the correct COM port assigned to your Demon.

  4. Save the settings and close the window.

If multiple ports are available, you can try the second port first. If it does not connect, try the first.

The correct port depends on your particular device and Windows configuration.

Make sure the appropriate USB drivers are installed.

C. Snake Emulator (Snake OBD1 EMU / Snakemu)

Snake Emulator devices also support realtime tuning and datalogging in Honda Tuning Suite.

However, the correct configuration depends on which Snake hardware and operating mode you are using.

Snake OBD1 EMU — Native HTS Connection

For compatible Snake OBD1 EMU hardware using HTS 2.22 or newer:

  1. Open File → Settings → Emulator/Datalogging.

  2. Select Snake OBD1 EMU.

  3. Save your settings and close the window.

With a supported native Snake connection, HTS can communicate directly with the device without manually selecting COM ports or installing separate serial drivers on supported Windows systems.

Snakemu V2 — Demon or Ostrich Protocol

Some Snake emulator setups use the SnakeTool utility to select their communication protocol.

If your device uses SnakeTool:

  1. Open SnakeTool and check which protocol your emulator is using.

  2. Select Demon or Ostrich mode, as appropriate.

  3. Note the COM port assignments displayed by SnakeTool.

  4. Close SnakeTool before opening HTS.

  5. Open File → Settings → Emulator/Datalogging.

Select the matching option:

  • Demon mode: Select Moates Demon.

  • Ostrich mode: Select Moates Ostrich.

Assign the appropriate COM ports.

Demon mode normally uses a single COM port, while Ostrich mode may use separate ports for emulation and datalogging.

For compatible Snakemu V2 setups, enable Use Fast Emulator Protocol when instructed by the device's setup guide.

We generally recommend Demon mode for Snakemu V2 because it simplifies connection and COM port configuration.

The native Snake OBD1 EMU setting and the SnakeTool Demon/Ostrich protocol settings are not interchangeable for every Snake device. Use the configuration appropriate for your exact model.

Step 2: Configure Your Wideband O2 Sensor

A wideband O2 sensor is essential for accurate fuel tuning, especially on modified or turbocharged engines.

Without reliable AFR readings, making precise fuel adjustments becomes guesswork.

In HTS:

  1. Go to File → Settings → Wideband.

  2. Select your wideband manufacturer and model.

  3. Select the correct ECU input where the analog signal is connected.

Common locations include:

  • D14: Commonly used for wideband input.

  • D10: Another possible input depending on ECU wiring and configuration.

Select whichever input your wideband is actually connected to.

The correct analog voltage calibration must also match your wideband controller.

Please let DGTune know:

  • Your wideband brand and model.

  • Which ECU input is being used (D14, D10, or another).

  • How the wideband is wired, if possible.

Verify Your Wideband Readings

Once the engine is running and HTS is connected:

  1. Go to Datalog → Start/Connect.

  2. Allow the wideband to warm up completely.

  3. Compare the AFR displayed on your physical gauge with the AFR shown in HTS.

Both readings should be very close.

For example, if your gauge reads 14.7 AFR but HTS displays 12.5 AFR, something is incorrect with the calibration, wiring, or input configuration.

Do not rely on inaccurate wideband data for tuning adjustments.

If your readings do not match, let us know how far apart they are.

Step 3: Open and Upload Your Tune (Emulator Setups Only)

This step applies to Moates Demon V1, Demon V2, and compatible Snake Emulator setups.

If you have a standard chipped ECU with a USB datalogging cable only, skip the upload instructions and continue to Step 4.

Open Your DGTune File

  1. Open Honda Tuning Suite.

  2. Go to File → Open.

  3. Select the tune file provided by DGTune.

  4. Make sure your laptop is connected to your emulator.

  5. Verify that the correct emulator and COM port settings are selected.

Connect and Upload

Go to:

Emulator → Connect

Once connected, select:

Emulator → Upload ROM

Or, depending on your HTS version:

Upload Base ROM & Calibration

Wait until the upload completes successfully.

Ignition requirements vary by emulator.

For the Moates Demon setups covered by our standard DGTune procedure, begin with the ignition completely OFF and the key removed, unless instructed otherwise for your particular hardware.

Some Snake Emulator configurations require or work better with the ignition ON during upload. Follow the connection procedure for your specific Snake model.

Never disconnect the emulator while an upload is in progress.

Verify the Tune Was Uploaded

Once the upload finishes:

  1. Turn the ignition OFF and remove the key.

  2. Disconnect the USB cable from the emulator.

  3. Leave the ECU connected to the vehicle normally.

  4. Attempt to start the engine without the laptop connection.

This helps confirm the emulator can retain and run the uploaded calibration independently.

Keep in mind that Demon V1 uses battery-backed memory, while Demon V2 uses nonvolatile storage. If your Demon V1 loses its tune after power is removed, check its backup battery and device configuration.

If the engine starts and stays running, continue to Step 4.

If it does not start or cannot remain running, skip to Step 5.

Step 4: Record a Datalog If the Engine Runs

These instructions apply to compatible cable-only datalogging, Moates Demon V1/V2, and Snake Emulator setups.

Connect to Live ECU Data

With the engine running:

  1. Connect your USB datalogging cable or emulator to your laptop.

  2. Open Honda Tuning Suite.

  3. Open the matching tune file provided by DGTune.

  4. Confirm the correct communication settings.

  5. Go to Emulator → Connect, if required for your hardware.

  6. Go to Datalog → Start/Connect.

You should begin seeing live ECU data updating in HTS.

Remember: If you are using cable-only datalogging, you are connecting to record data, not to upload a ROM.

Record a Cold-Start Datalog

A complete cold-start and warm-up log is one of the most useful datalogs you can provide.

It helps us review startup fueling, idle behavior, warm-up enrichment, and temperature-related corrections.

For a proper cold-start datalog:

  1. Allow the engine to cool down completely.

  2. Connect your laptop and establish communication in HTS.

  3. Go to Datalog → Start/Connect.

  4. Click Record before starting the engine.

  5. Start the engine and allow it to idle.

Let the engine warm up to approximately 180°F (82°C).

Once warmed up, continue recording for approximately 10–15 additional minutes at idle, if the engine is operating normally.

The longer the useful datalog, the more information we have to work with.

Keep monitoring coolant temperature and AFR throughout the process. Perform stationary logging outdoors in a well-ventilated location, never inside a garage.

Record Some Light Throttle Changes

If the engine runs normally, you can also record a few gentle RPM changes.

While safely parked in neutral:

  1. Begin recording a datalog.

  2. Slowly increase RPM toward approximately 3,000 RPM.

  3. Let RPM return to idle.

  4. Repeat a couple of times.

Do not aggressively rev the engine or enter boost until the tune and engine operation have been verified.

Save Your Datalog

When finished:

  1. Go to Datalog → Stop.

  2. Click Save.

  3. Select Yes if prompted.

  4. Name the file and save it to your laptop.

Your datalog will typically be saved as an .RLOG or .LOG file, depending on the HTS version. We prefer .RLOG.

Send us the datalog file — NOT the .BIN tune file.

Step 5: What If Your Engine Does Not Start or Stay Running?

Even if your engine does not start or struggles to maintain idle, a datalog can still provide valuable information.

Record a No-Start or Stalling Datalog

  1. Turn the ignition OFF and remove the key.

  2. Connect your ECU datalogging cable or emulator to the laptop.

  3. Open HTS and the matching tune file.

  4. Establish communication using the correct device settings.

  5. Go to Datalog → Start/Connect.

  6. Click Record, when supported, before attempting to start.

Turn the ignition ON and crank the engine.

If the engine starts but immediately stalls, carefully apply some throttle to see whether it can remain running.

Approximately 25%–50% throttle pedal input may be needed in some cases, but keep engine RPM controlled and avoid excessive or sustained revving.

If the engine can remain running for a minute or two without showing signs of damage or unsafe operation, that information may help us diagnose the issue.

Do not continue running the engine if you notice:

  • Abnormally lean AFR readings.

  • Severe misfires.

  • Mechanical knocking or unusual engine noises.

  • Overheating.

  • Any other signs of unsafe engine operation.

When finished:

Datalog → Stop → Save

Send the saved datalog to DGTune.

Even a short log capturing cranking, startup, or stalling can help us identify the next troubleshooting steps.

Step 6: Troubleshooting HTS Connection Problems

If you cannot connect to your ECU, go through the following checks before contacting support.

1. Verify the ECU Hardware

For applicable conventional chipped ECU configurations:

  • J12 jumper is completely removed.

  • CN2 datalogging header is properly installed.

  • The ECU has the necessary datalogging support.

  • The cable or emulator is installed and connected correctly.

Software settings cannot compensate for missing hardware or an improperly prepared ECU.

2. Select the Correct Device in HTS

Use the appropriate setting for your setup:

Your ECU Hardware HTS Emulator Setting
Chipped ECU with USB datalogging cable only Moates Ostrich / Ostrich
Moates Demon V1 Moates Demon
Moates Demon V2 Moates Demon
Native Snake OBD1 EMU Snake OBD1 EMU
Snakemu V2 configured in Demon mode Moates Demon
Snakemu V2 configured in Ostrich mode Moates Ostrich

Some device versions and firmware configurations may require different options.

3. Verify Your COM Port

For hardware that uses manual COM port selection:

  1. Open Windows Device Manager.

  2. Expand Ports (COM & LPT).

  3. Identify the port assigned to your USB device.

  4. Open HTS and select that same COM port.

  5. Attempt to connect again.

If necessary, disconnect the USB cable and observe which COM port disappears. Reconnect it and see which port returns.

This can help identify the correct port.

4. Make Sure Your USB Drivers Are Installed

Many Moates devices and USB datalogging cables use FTDI drivers.

If you're using Windows 10 or Windows 11, ensure the proper drivers are installed.

Download FTDI USB Drivers for Windows 10/11 (64-bit)

After installation:

  1. Disconnect your USB cable.

  2. Reconnect the cable.

  3. Restart HTS.

  4. Verify the COM port assignment.

  5. Try connecting again.

Note: Native Snake OBD1 EMU connections supported by HTS 2.22 may not require manually installing drivers or selecting COM ports. Other Snake modes and cable-only setups may still require them.

5. Reset Older Moates Demon Devices (If Necessary)

Only use this procedure if you're having connection or compatibility issues with an older Moates Demon.

Some older Demon devices were previously configured for Neptune, Crome, or eCtune and may require a reset when switching to HTS.

Moates provides a utility for this purpose:

Moates Demon/Ostrich Reset Utility

  1. Download and open the utility.

  2. Connect your Moates Demon.

  3. Follow the reset procedure.

  4. Select the compatible eCtune configuration if directed for your HTS setup.

  5. Reopen HTS and attempt to connect.

Warning: This procedure may clear the existing device configuration and stored tune. Make sure you have a copy of your calibration before proceeding.

Do not use this reset utility on a standard USB datalogging cable or incompatible Snake Emulator hardware.

6. Check the Moates Demon V1 Backup Battery

If you have an older Demon V1 and the device repeatedly loses its stored tune, check the backup battery.

Demon V1 relies on battery-backed memory, while Demon V2 uses nonvolatile storage.

A weak or failing battery can cause tune-retention problems.

Verify the correct battery specification before replacing it. Disconnect the device from power and handle ECU electronics carefully.

7. Check Your Snake Emulator Configuration

If you're using Snake Emulator hardware and cannot connect:

  • Verify which Snake model you have.

  • If using native Snake OBD1 EMU mode, select the appropriate native option in HTS.

  • If using Snakemu V2 with SnakeTool, confirm whether Demon or Ostrich protocol is selected.

  • Make sure the HTS emulator setting matches the selected protocol.

  • Verify COM port assignments when required.

  • Close SnakeTool before attempting to connect through HTS.

  • Confirm that your software and emulator firmware are compatible.

If connection problems persist, the issue may involve ECU socketing, emulator hardware, USB communication, firmware, or another ECU-related problem.

Step 7: Send Your Datalogs to DGTune

Once you've recorded your datalogs, email them to:

support@dgtune.shop

Please include:

  • Your DGTune order number.

  • Your vehicle, engine, and ECU information.

  • Your hardware setup: cable-only, Demon V1, Demon V2, or Snake Emulator.

  • Your saved .RLOG or .LOG datalog files.

  • Your wideband brand/model and input location.

  • A short description of the issue you are experiencing.

Whenever possible, provide separate datalogs for:

  • Cold startup and warm-up.

  • Fully warmed-up idle.

  • Light throttle and gentle RPM changes.

  • Any hesitation, stalling, or other drivability issues.

Longer, accurate datalogs typically give us a better understanding of how your engine operates.

Why Datalogging Matters

At DGTune, every custom tune is built using the engine specifications and modifications provided during your order.

However, no two engines are exactly alike.

Injector characteristics, fuel pressure, sensors, wiring, engine condition, and other variables can all affect how an engine responds.

That's why datalogging is so valuable.

It allows us to make informed tuning decisions based on actual engine data instead of assumptions.

Keep in mind that a tune cannot repair mechanical issues, vacuum leaks, wiring faults, incorrect fuel pressure, failing sensors, or other underlying engine problems.

Before requesting tuning adjustments, make sure your engine and ECU are functioning correctly.

Final Thoughts

Whether you're using a basic chipped ECU with a USB datalogging cable or a complete emulator setup, Honda Tuning Suite provides valuable information about how your engine is running.

The most important things to remember are:

  • Cable-only datalogging: Select Ostrich, configure the proper COM port, and open your DGTune tune file to follow the engine's activity on the maps. You cannot upload or change the chip tune.

  • Moates Demon V1/V2: Select Moates Demon, configure communication, and use the supported ROM upload and datalogging functions.

  • Snake Emulator: Select the correct native Snake option or matching Demon/Ostrich protocol depending on your emulator model.

  • Wideband: Make sure your AFR readings are accurate and match your physical gauge.

  • Datalog files: Save and send us your actual .RLOG.

If you need assistance with your setup, contact our support team with your order number and hardware information.

We're here to help you get the most out of your DGTune experience.

DGTune specializes in Honda and Acura OBD1 ECU tuning, chipped ECUs, ECU socketing, and remote tuning.

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