Your check-engine light is not a problem to be cleared. It is a message from the car's onboard computer that one of its sensors is reporting a value outside expected range. The cheap code reader at the parts store will tell you the code; it will not tell you the cause.
We run factory diagnostic software for every European make: VAG-COM (VCDS) for VW and Audi, BMW ISTA, Mercedes XENTRY, Porsche PIWIS, Volvo VIDA. We also keep current generic OBD-II equipment for everything else. The factory software reads not just the current code but the fault history, the freeze-frame data, and the live sensor stream — which is what actual diagnosis requires.
How much does diagnosis cost?
Standard diagnosis is $145, which covers up to 90 minutes of diagnostic time with our factory equipment. The diagnosis fee is fully applied toward the repair if you proceed with the recommended work. Complex diagnoses (intermittent faults, electrical gremlins, network communication issues) may require additional time, which we'll discuss with you before proceeding — we don't go past your authorized amount without calling.
What's included in a diagnosis?
- Scan
- Factory software for your make, all modules — not just engine
- History
- Stored faults and frequency, not just current codes
- Live data
- Sensor values watched in real time, often during a road test
- Report
- Written diagnosis with photos and a repair quote, sent to your phone
Can't I just read the code with a parts-store scanner?
You can. The parts-store scanner reads the OBD-II generic code (P0420, P0301, etc). That's the symptom — not the cause. The factory diagnostic equipment reads the manufacturer-specific code, the freeze-frame data from the moment the fault triggered, the live sensor data while the fault is active, and the fault history.
A P0301 misfire on cylinder 1 can be a coil, a plug, an injector, low compression, a vacuum leak, a wiring fault, or a software issue — the parts-store scanner can't tell you which. The factory diagnostic equipment can, in most cases, in twenty minutes.
Frequently asked questions
My check-engine light went off on its own. Do I still need diagnosis?
The light went off because the fault condition stopped triggering — but the stored fault history is still in the car's computer. We can read the fault history and the freeze-frame data even after the light clears. If a fault is happening intermittently, you probably want to know about it before the light comes back on at an inconvenient moment.
Do you do electrical-system diagnosis?
Yes. Electrical-gremlin diagnosis is some of the hardest work in the trade and we charge for the time it takes. Most network communication faults (CAN-bus issues on BMW and Mercedes, MOST-bus on older Audi) are resolved within two to three hours of our shop time once we identify the affected module.
Can you do coding and programming?
Yes for VW/Audi (VAG-COM coding), BMW (ISTA coding for most jobs), and Mercedes (XENTRY for most). For 992-series Porsche jobs that require PIWIS coding we send out to a Porsche-only shop on Federal Boulevard who has the current PIWIS subscription.