Seeking Advice on Troubleshooting Black Smoke, Engine Issues, and Poor Fuel Efficiency in 2006 Diesel Mazda Atenza

Hey! I've had a similar issue with my 2004 Mazda Axela, so maybe we're in the same boat. Just so you know, my car expertise is probably somewhere around 'low to some experience'. The issue turned out to be a faulty wiring harness/plug in my case. The symptoms you've mentioned, especially the check engine light and engine instability, rang a bell. I took the car to my local workshop, explained the issue and they tracked it down for me. Cost me a bit of cash, about 95 Euro to get it all fixed up. By the way, do you know the mileage, maintenance history, any engine modifications or recent repairs on your Atenza? More info would help in making a solid guess about what's up with your car. Hope this helps! Cheers!

Hey there, Thanks for sharing your experience. That's a possibility I hadn't thought of! I'll take a note to check on the wiring harness the next time I visit a workshop. As for your questions, my Atenza has clocked 293351 KM, no engine modifications or recent major repairs done. Honestly, it has been humming along nicely after its last service, until these symptoms cropped up suddenly. I'll update once I have some more information. Cheers!

Good day again, No problem at all! Always happy to participate and help sort things out. Looking at your mileage, it's possible that certain engine compartments like the fuel pump could be worn out, seeing degradation over the years. Your guess might not be too off then. Another thing you could consider is having your injectors cleaned, because sometimes dirty or clogged fuel injectors could also cause some of the problems you've mentioned. Although my problem was with the wiring harness, I initially guessed it's the fuel pump too. So, it does seem like we're sailing in the same boat when it comes to playing the guessing game! I would recommend focusing on getting that check engine light scanned ASAP. The error codes will help drill down on what exactly might be causing the trouble, and it's usually the quickest route to a targeted repair. If you've got any update after your check, drop a line here. Curious to know what's up. Keep the spirits up! We'll sort this out. Cheers!

Hey! Cheers for the additional tips and guidance! Focusing on the fuel pump and injectors sounds like pretty sensible advice to me. That check engine light is certainly my top priority right now. I agree, getting those error codes is key. Once I've got them, I'll put them up here for further interpretation and advice... who knows, there might be someone out there who has a more precise idea what they mean. Yes indeed, it's quite a guessing game. But hey, troubleshooting is part of the journey, right? Anyway, I'll keep you posted. Thanks again for your help, really appreciate it! Ride on! Cheers!