I hesitate to write this, as it will probably make me sound like a moron, but maybe my experience will help others. I’ve owned my ecodiesel for two years and have loved it. It tows great, gets good gas mileage, is comfortable and fun to drive with a tune. When I test drove it before I bought it, I noticed a faint smell of diesel exhaust and asked the salesmen who was in the car with me and he dismissed it as just warming up. I bought it anyway and it quickly turned to summer and the smell mostly disappeared. I noticed in the winter that it started coming back and I tried to ignore it and it mostly went away at highway speeds. I shrugged off as a quirk of diesels. Fast forward to a year and a half later and I finally decided to look into it because I have a son now and I recently had him in the car during a regen and it was smoking at stop lights and filling the cabin with a horrible smell. It turns out that what I believe is the EGT sensor 1 was completely missing the net that held it in. It was luckily still on the cable and I was able to reinstall it. I have no idea how the sensor just loosely sitting in an open hole didn’t throw any codes, but that seems to have been the issue. With the nut reinstalled, It miraculously smells clean and clear in my cabin like it never has before. I am worried as hell as to what I’ve exposed my family to over this period, but luckily is hasn’t been a commuter for me until 6 months ago and hopefully a limited exposure for them. In any case, learn from my mistakes. If your smelling exhaust fumes, don’t put up with it. Pictures of the sensor below.