When to Diagnose Before Tuning

Active or Pending Fault Codes

If your diagnostic scan reveals active fault codes related to the engine, turbo, fuel system, or emission controls, those faults must be resolved before tuning. A calibration cannot compensate for a hardware failure, and tuning a faulty engine risks compounding the problem or masking the root cause.

High-Mileage Vehicles

Engines above 150,000 km may have increased blow-by, worn turbo seals, or degraded injectors that affect baseline performance. A compression test, turbo-play check, and injector balance test can confirm whether the engine is mechanically sound enough to benefit from a tune without introducing reliability concerns.

Unknown Modification or Tuning History

If you have purchased a used vehicle and are unsure whether it has been previously tuned or had parts replaced with non-OE components, a diagnostic review can uncover hidden modifications. Identifying these before calibration ensures the file is written for the actual state of the vehicle, not an assumed one.

Requesting a Diagnostic Review

Submit a diagnostic request through the portal with your scan results and a brief description of any symptoms. Our team will advise whether the vehicle is ready for calibration or if specific repairs should be addressed first. This step can save significant time and cost in the long run.

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