If a dealer inspected the car and found *nothing* wrong, that's highly unusual and suggests a few possibilities:
* Intermittent Problem: The issue might be intermittent, meaning it only occurs under specific conditions (high temperature, low fuel, specific RPM range). The problem may not have manifested during the dealer's inspection.
* Poor Diagnosis: The dealer may not have properly diagnosed the issue. They might have only performed a cursory check or missed something. Getting a second opinion from another mechanic is strongly recommended in this case.
* Faulty Sensor: A sensor might be providing inaccurate data, leading to the reduced engine power light. These sensors can be tricky to diagnose as they might only be slightly off, not failing entirely.
* Software Glitch: Less common, but a software glitch within the car's computer could be causing the light to illuminate without a true underlying mechanical problem. A software update might resolve this (if applicable).
* Cleared Codes, Not Fixed Problem: The dealer might have simply cleared the trouble codes from the computer without addressing the root cause. The light will return if the problem persists.
What to do:
1. Get a second opinion: Take your car to a different, reputable mechanic or an independent shop. Explain the situation and emphasize that the dealer found nothing.
2. Obtain a copy of any diagnostic reports: If the dealer ran any diagnostics, insist on a copy of their report. This might shed some light on what they checked.
3. Mention specific conditions: When describing the problem to the mechanic, mention any specific conditions under which the light comes on (e.g., acceleration, engine temperature, etc.).
4. Consider an OBD-II scanner: A relatively inexpensive OBD-II scanner can read the trouble codes yourself. This gives you a starting point for researching the possible causes. However, the codes alone are not always a definitive diagnosis.
The "reduced engine power" light is a serious warning. Ignoring it could lead to significant engine damage. Don't delay in getting this properly investigated.
