B58 Engine | 2018 BMW 540i

Let’s talk shop. A customer came in looking to have their 2015 Fiat 500 Pop checked out because it had previously failed a smog check. Apparently, the other shops that the customer visited couldn’t tell what was wrong. So naturally, we needed to check the car out and see what issue we might run into so that the customer wouldn’t be repeating the same problem. A failed smog test? A repair that others couldn’t figure out? Sounds like a job for Euro Auto Tech. Let's dive in. Diagnosis We started scanning the Fiat for fault codes so that we would know which direction to start going in. The scans revealed code P0441, an EVAP System Incorrect Purge Flow. Then a code P0456, an EVAP System Very Small Leak. Now, instead of just clearing the codes and sending the car back on its way, we wanted to go after the root cause of the problem. During our EVAP smoke testing, we found that the leak detection pump was faulty and unable to hold pressure. We also saw smoke exiting through the intake pipe. Further testing confirmed our suspicion that the purge valve was not sealing right, allowing smoke to pass through when it should have remained closed. What Needs to Be Done To restore the EVAP system and help the vehicle maintain pressure, we recommended replacing the leak detection pump and purge valve. Also, while inspecting the vehicle, we found another safety concern: the front headlight pigtail was melted into the bulb socket. So we recommended replacing the pigtail and front headlight bulb to restore operation and prevent any kind of heat-related damage. Pro Tip: When you see codes like P0441 and P0456, don’t assume that the fix is just replacing a gas cap or clearing codes. Evap Problems can come from multiple components; making sure the right diagnostic testing is done is what separates guessing from knowing. Things like a smoke test, pressure test, and checking each component will help pinpoint the real problem. Result:  At the end of the day, the customer drove out of our lot not having those same EVAP problems. Another day, another happy customer. Catch us every Friday for more shop talk. And remember: Good work ain’t cheap. Cheap work ain’t good. Euro Auto Tech & Smog | European Specialist | 7633 El Cajon Blvd #217, La Mesa, CA 91942

Don’t wait for the check engine light to tell you something is wrong. Follow your maintenance schedule and have your Mercedes inspected regularly every 5k miles.