The COBB Project Green Speed update ended the old easy WRX recipe: bolt on an aftermarket j-pipe, flash a COBB Stage 2 map, suppress the emissions-related codes, and call the build done.
The Accessport still works. COBB still offers OTS maps, current Stage packages, CAN-based flex fuel systems, and custom tuning through its Protuner network. The tune, vehicle, and parts list now have to match much more closely.
Quick answer:
- Current COBB OTS maps require the vehicle, fuel, and hardware specified in their map notes, including any listed exceptions.
- Current COBB WRX OTS maps do not support aftermarket downpipes or j-pipes.
- The current COBB Stage 2 path retains the factory catalytic hardware.
- Flex fuel has returned for supported VA and VB WRXs through CAN-based hardware.
- Custom tuning remains available through COBB Protuners, within the current software limits.
- Updating an Accessport does not erase maps already stored on it, but a legacy map with removed emissions-related features cannot be revised.
On this page
- What Did the COBB Project Green Speed Update Change?
- What Changed for an Existing WRX Build?
- What Did the 2024 EPA Settlement Change?
- Does the COBB Accessport Still Work?
- Can I Still Use Accesstuner?
- Can I Use an Aftermarket Downpipe or J Pipe?
- What About Catless Downpipes?
- What Happened to WRX Stage 2?
- Can I Still Use Flex Fuel?
- What Can Tuners Still Tune?
- Is There a Supported Green Speed Workaround?
- The Current COBB WRX Path
- FAQ
What Did the COBB Project Green Speed Update Change?
Project Green Speed is COBB’s emissions-compliance program for its parts, OTS maps, and Accesstuner software. The changes arrived in stages, including California OTS-map restrictions in 2021 and a major Accesstuner update in April 2022. COBB’s April 2022 update documents the software changes; its Green Speed FAQ explains what happened to existing Accessports and stored maps.
For a WRX owner, the before-and-after looks like this:
| Area | Old COBB path | Current COBB path |
|---|---|---|
| Downpipes and j-pipes | Aftermarket pipe plus a matching Stage 2 OTS map | Factory j-pipe for current COBB WRX OTS-map support |
| Emissions-related DTCs | Selected codes could be disabled in a map | Current Accesstuner software does not offer those adjustments |
| Flex fuel | Legacy VA kits used an analog TGV-related ECU input | Current kits send ethanol-content data through a CAN Gateway |
| Stage 2 | Commonly centered on an aftermarket j-pipe | Current packages use airflow, cooling, and boost-control parts while retaining factory catalysts |
That last point catches people out. A 2018 parts list can still look perfectly normal in a forum thread or used-car ad, yet have no current COBB OTS map. A custom-tune route depends on the exact hardware and current Accesstuner limits.
What Changed for an Existing WRX Build?
| If your WRX has… | What the update changed | What that means now |
|---|---|---|
| A legacy map stored on the Accessport | The software update did not erase the map or change how it runs. A new revision is subject to the current Accesstuner limits. | Later hardware changes need a calibration written for that hardware. |
| An aftermarket j-pipe or downpipe | That old Stage 2 combination is outside the current COBB WRX OTS-map path. | Current COBB OTS maps require the factory j-pipe. |
| Legacy analog flex fuel | The old analog Subaru feature is not part of current Accesstuner software. | Current CAN kits and calibrations are model-year and transmission specific. |
| TGV, EGR, or secondary-air changes | A calibration cannot use current Accesstuner controls to suppress the related emissions DTCs or alter those system functions. | A stored legacy map can keep running. A revised COBB map cannot retain deleted or masked systems. |
| A stock car | Current COBB OTS maps and matched packages remain available for supported applications. | Each package and map has its own specified hardware. |
COBB’s April 2022 update identifies DTCs, catalysts, EGR, TGV, secondary-air injection, and analog Subaru flex fuel among the Accesstuner changes. Those limits apply to new and revised COBB-based calibrations.
COBB’s FAQ confirms that the 2022 Accesstuner changes did not remove maps already stored on an Accessport or alter how an existing map made the car run. They changed what could be created or revised with updated tuning software.
If a compatible legacy map is already stored on your Accessport, the Green Speed update does not delete it or stop the Accessport from flashing it. Affected downpipe, j-pipe, and Stage-package maps are no longer preloaded or available to download from COBB.
What Did the 2024 EPA Settlement Change?
Project Green Speed came first. The federal settlement made the compliance obligations explicit.
On September 16, 2024, the EPA and Department of Justice announced a Clean Air Act settlement with COBB. The settlement requires COBB to stop selling the affected defeat-device products, remove delete features from its software, and stop technical and warranty support for those products. It allows COBB to continue selling products covered by a CARB Executive Order. The EPA’s COBB settlement summary provides the full compliance terms.
The settlement requires a narrower current COBB support path:
- Discontinued downpipes and other affected products no longer receive COBB technical or warranty support.
- Current software cannot be used to create emissions-delete tunes.
- Current products and calibrations follow documented emissions-compliance paths.
Does the COBB Accessport Still Work?
Yes. On a supported WRX, the Accessport can still flash compatible OTS or custom maps, display live engine data, record datalogs, and read or clear diagnostic codes. Our WRX Accessport guide covers OTS maps, custom tuning, gauges, logging, and used-device checks.
Accessport part numbers are specific to the model year and transmission, and a used unit must be uninstalled from its previous car. COBB’s map notes set the vehicle, fuel, and hardware combination each map supports.
Can I Still Use Accesstuner?
COBB paused new end-user Accesstuner training and software requests in 2022. Existing trained users kept access; new custom work goes through a Protuner.
One alternative is Atlas open tuning, a laptop-based route for supported VA and VB WRXs. Atlas also does not support disabling emissions-related DTCs or systems.
Can I Use an Aftermarket Downpipe or J-Pipe?
COBB’s current WRX Stage packages and supporting calibrations retain the factory j-pipe and catalytic hardware. An Accessport that already has an old j-pipe map stored can still flash it. New devices do not include those maps, and COBB no longer offers them for download.
A custom tune may still be an option for a WRX with a catted j-pipe when a COBB Protuner accepts the hardware and can calibrate it within current Accesstuner limits. COBB can alter an existing custom map, but the revision cannot include disabled emissions codes or the old analog flex-fuel setup.
Some aftermarket j-pipes use GESi catalysts. COBB discontinued its GESi j-pipes and their associated OTS maps for the 2015-2021 WRX in 2022. COBB has no CARB EO-approved aftermarket j-pipe for the FA20DIT WRX; its current 50-state NexGen path retains the factory j-pipe.
For package-by-package detail, see the updated WRX Stage 2 kits guide.
What About Catless Downpipes?
Current COBB software cannot provide the catalyst-monitor and DTC changes a catless setup commonly relied on. On a street-driven WRX, removing required catalytic hardware also creates an emissions-enforcement and inspection problem. Keep the factory catalytic system when building around a current COBB map.
What Happened to WRX Stage 2?
Stage 2 survived, but its COBB meaning changed. A current VA NexGen package or VB Stage 2 package retains the factory catalytic hardware; the exact intake, intercooler, charge-pipe, and boost-control parts vary by application. COBB lists the current parts and supported applications on its VA NexGen and VB Stage 2 pages.
Older WRX Stage 2 builds often use an aftermarket j-pipe and legacy map. A catted-j-pipe car follows the custom-tune path above, rather than a current COBB OTS or NexGen package.
For the complete terminology breakdown, see what WRX stages mean now.
Can I Still Use Flex Fuel?
Yes. The legacy VA flex-fuel kit routed ethanol-sensor data through a TGV-related ECU input. Green Speed removed that tuning route from new and revised COBB maps.
Current CAN kits send ethanol-content data through the Gateway. Fuel-pressure data can join that signal when the matching sensor is fitted.
| WRX application | Current COBB-branded support | Detail that matters |
|---|---|---|
| 2015-2017 VA, USDM 6MT | CAN Flex Fuel | Uses the early VA-specific Gateway harness |
| 2018-2021 VA, USDM 6MT | CAN Flex Fuel | Uses a different Gateway harness from 2015-2017 |
| 2022-2025 VB, USDM 6MT/CVT | CAN Flex Fuel | COBB’s current US flex-fuel product listing covers these model years |
| 2022-2026 VB, Australian market | CAN Flex Fuel | Separate Australian-market hardware and application list |
VA kits include the ethanol sensor and CAN Gateway; fuel-pressure hardware varies by bundle. COBB’s OTS maps require the complete configuration in their map notes. These kits are not legal for sale or use in California while CARB EO coverage is pending. Compare COBB’s 2015-2017 kit, 2018-2021 kit with fuel-pressure sensing, and 2022-2025 US-market VB kit.
For a package-by-package comparison, see the WRX CAN flex-fuel kit guide.
What Can Tuners Still Tune?
COBB Protuners can still create custom calibrations for supported WRXs. A custom map can account for supported hardware, local fuel, and an individual car, within the current Accesstuner limits.
Map availability depends on the exact model year, transmission, fuel, supporting parts, and whether the car uses an OTS map, a pump-gas custom tune, or CAN flex fuel. California registration also requires CARB EO coverage for the exact parts.
If you already know you want a custom calibration, compare the logging and shop time involved in a WRX e-tune versus a dyno tune.
Is There a Supported Green Speed Workaround?
No. Current COBB software cannot restore emissions-delete functions.
The Current COBB WRX Path
Project Green Speed ended COBB OTS support for the old aftermarket-j-pipe Stage 2 setup and limited the emissions-related changes available in custom maps. Current COBB WRX options are factory-j-pipe OTS and NexGen packages, CAN flex fuel on supported cars, and custom calibrations for hardware a Protuner supports within those limits.
FAQ
Did Project Green Speed kill WRX tuning?
No. WRX owners can still use supported Accessport maps, current COBB packages, CAN Flex Fuel kits, and Protuner calibrations. Current COBB WRX OTS maps no longer support the old aftermarket-downpipe recipe, and current Accesstuner software does not offer emissions-related DTC adjustments.
Is COBB tuning illegal?
No. Current COBB maps, parts, and Protuner calibrations remain available for supported applications. Emissions-delete tunes and the affected defeat-device products fall outside COBB’s current software and support path.
Can I still run a COBB Accessport on my WRX?
Yes, if your WRX is supported by the correct Accessport part number and you use maps that match your vehicle and parts.
Will updating my Accessport erase my maps?
No. COBB says the Green Speed Accesstuner update did not change Accessport functionality or erase maps already stored on the device. A legacy map with removed emissions-related features may not be editable or revisable in the same form.
Can COBB send me a map for an aftermarket downpipe?
Not with a current COBB OTS map. COBB’s current Stage packages and supporting maps retain the factory j-pipe. A COBB Protuner may be able to calibrate a catted aftermarket j-pipe within current software limits, but a revised map cannot use emissions-code suppression.
Was the COBB GESi j-pipe discontinued?
Yes. COBB discontinued its 2015-2021 WRX GESi j-pipes and their associated OTS maps in 2022. Its current 50-state NexGen package retains the factory j-pipe.
Can a COBB tune turn off P0420?
No. COBB removed DTC suppression for catalyst-related codes from current Accesstuner software, so a revised COBB map cannot turn off a catalyst-efficiency code.
Is flex fuel back for the WRX?
Yes, but application limits matter. COBB’s current VA release covers US-market 2015-2021 WRX six-speed cars. Its current US-market VB product page lists 2022-2025 manual and CVT applications. COBB separately lists Australian-market VB flex-fuel support through 2026.
Can I still pass emissions with a modified WRX?
Passing depends on the exact parts and calibration, completed readiness monitors, and the local test. California parts need applicable CARB coverage.
Is there a Green Speed workaround for a deleted emissions system?
Current COBB software cannot restore emissions-delete controls or suppress the related DTCs.