Most shops plug in a code reader and start replacing parts. We treat a diagnostic code as a starting point — not an answer. Proper diagnostics means reading live data, testing components, and confirming the actual failure before anything gets replaced.
We pull and interpret every stored and pending code. A P0420 or P0300 tells us which system to investigate — not which part to order.
We monitor real-time sensor data — fuel trims, oxygen sensor response, misfire counts, injector pulse width — to see exactly how your engine is operating under different conditions.
Suspicious sensor? Failing actuator? We test components directly before condemning them. This eliminates guesswork and prevents replacing parts that were never the problem.
Intermittent electrical issues are the hardest to diagnose. We use wiring diagrams, voltage drop testing, and oscilloscopes to find faults other shops miss.
Before we quote any repair, we confirm the diagnosis. You know exactly what is wrong and why before you approve a single dollar of work.
Every job at C&D follows the same process — diagnose, quote, repair, verify. See how it works →
Diagnostic fees at C&D Automotive run $75-150. If you authorize the repair, the fee is applied to your bill.