Navigating the world of car diagnostics can be tricky, especially with older models. If you’re a proud owner of a 1999 Subaru WRX GC8 and are scratching your head about OBD2 compatibility, you’re not alone. Many enthusiasts find themselves in the same boat, wondering what type of OBD code reader will actually work with their beloved GC8. Let’s dive into the specifics of diagnosing your GC8 and selecting the right tools for the job.
Standard OBD2 readers, while widely used on modern vehicles, might leave you stranded when you try to connect them to your GC8. This is because the 1999 GC8, a gem from the late 90s, doesn’t fully adhere to the OBD2 protocols we see in today’s cars. Instead, it often utilizes a system known as SSM, or Subaru Select Monitor. This difference is crucial in understanding why your friend’s generic OBD2 reader, which works perfectly on a 2010 FG Falcon, might fail to communicate with your GC8’s AE801 ECU.
So, what are your options when a standard OBD2 reader falls short? The good news is that the GC8 is still diagnosable, just through different methods. Here are a couple of paths you can explore to read those crucial codes and get to the bottom of any issues, like the starting problem mentioned, where fuel and spark are present, but the engine refuses to fire.
One commonly suggested solution within the Subaru community involves utilizing a VAG-COM cable, originally designed for Volkswagen Audi Group vehicles. Paired with software like ECUExplorer or FreeSSM, this combination can unlock diagnostic capabilities for your GC8. The VAG-COM cable, specifically those with an FTDI chip, acts as the necessary interface to communicate with the Subaru’s ECU via the SSM protocol. ECUExplorer and FreeSSM are free software tools that are designed to read Subaru specific data, including fault codes, and allow for real-time monitoring of engine parameters.
For those who prefer a more streamlined approach without needing a laptop constantly connected, the OBDKey device has been reported to work with GC8 models in SSM mode. Users have found it functional with apps like Torque for real-time data monitoring. However, it’s worth noting that fault code reading via Torque might be software-dependent and not a limitation of the OBDKey hardware itself. Further exploration with software like FreeSSM might be necessary to fully tap into the diagnostic potential for fault codes with OBDKey.
If you’re facing a no-start condition with your GC8, and suspect sensor issues, being able to read diagnostic codes is invaluable. While swapping ECUs, like trying an AE802, can be a troubleshooting step, it’s often more efficient to pinpoint the problem through diagnostics first. Remember, effective diagnosis saves time and money in the long run.
In conclusion, while your 1999 Subaru WRX GC8 might not be directly compatible with every generic OBD2 reader due to its SSM system, there are viable alternatives. Exploring options like a VAG-COM cable with ECUExplorer/FreeSSM or an OBDKey device can provide the diagnostic access you need. These tools, favored by the Subaru community, can help you understand your GC8’s health, read trouble codes, and ensure your classic WRX continues to run smoothly for years to come.
