Q: 2011 Audi SUV Q7 supercharger EPC LIGHT CAME ON THEN SAID DO NOT EXCEED ENGONE OVER 4000 TO ME WHAT IS THIS

When you kicked into passing (lower) gear, the engine was immediately heavily loaded. If there is any fault, or "weakness" in the ignition, fuel or air induction systems, such will become more readily apparent in those conditions. So, for example, you could have something as simple as worn spark plugs in need of service, fuel injectors that are getting clogged, a marginal oxygen sensor(s) and so forth but the problem only arises when the engine is heavily loaded. The EPC warning light may have gone out, but there are probably trouble codes that have been stored. To prevent an incipient issue from becoming a full blown malfunction, in your circumstance I would recommend that you have the car’s computer (PCM/ECM) scanned for codes and also evaluated using a standard automotive scanner to look at basic functions including oxygen sensor outputs, MAF values and so forth. If you desire that diagnostic, please refer to YourMechanic’s Check Engine Light diagnostic service page. If you request that service, the responding certified mechanic will come to your location, download the trouble codes, run the necessary tests and let you know exactly what has failed, or is on the verge of failing, and why. If you authorize the indicated repairs, the mechanic will perform that as well, again right at your location. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.