Mitsubishi Space Star: Black Smoke & Power Loss Mystery

Hey there! I had a similar issue with my 2020 Mitsubishi Eclipse Cross diesel last year. I've got some experience working on cars as a hobby mechanic. The symptoms you're describing sound exactly like what I experienced. Turned out the wiring harness to the boost pressure actuator was damaged in my case. My trusted mechanic found some frayed wires that were causing irregular signals. Got it fixed for about 155€, mostly labor costs since they had to carefully access and replace the wiring. Quick question though, what's your mileage and have you noticed if these symptoms get worse in any particular driving conditions (like highway vs. city driving)? This info might help confirm if you're dealing with the same issue I had. Hope this helps point you in the right direction! Let me know if you need any more details.

Hey! Thanks for sharing your experience. Currently at 85011 KM since my latest service about 2 months ago. To answer your question, it's definitely worse on highways, especially when trying to overtake. The black smoke and power loss become really noticeable above 100 km/h. Your wiring harness issue sounds quite similar to what I'm experiencing. Did you also notice the smoke and weird exhaust smell before getting it fixed? The repair cost seems reasonable, I'll have my mechanic check the wiring first before looking into other potential causes. Appreciate the help!

Hey again! Yeah, absolutely, I remember the black smoke and that funky exhaust smell all too well! It was actually one of the main things that got me worried with my Eclipse Cross. When I was trying to overtake on the highway, it was like driving through a fog bank of my own making. My symptoms were pretty much identical at highway speeds. I remember this one time trying to pass a truck, and my car just wouldn't give me the power I needed, super scary moment actually. The black smoke was way worse during those high-speed acceleration attempts, just like you're describing. My car was at around 78,000 KM when it happened, so pretty close to your mileage. The fact that you're experiencing it more on highways really sounds like the same wiring issue I had. When the wiring's damaged, the boost pressure can't regulate properly at higher speeds, which explains all these symptoms. Just a heads up, make sure your mechanic checks the whole length of the wiring harness carefully. In my case, they initially missed some wear near the connection point, and it took a second look to spot the actual problem. Keep me posted on what your mechanic finds! Would be interesting to know if it's the same issue.

Thanks so much for all the detailed info! That's really reassuring to hear that your symptoms matched mine so closely, especially the highway overtaking issues. It's kind of scary when you can't count on your car to give you power when you need it most. I've actually just booked an appointment with my mechanic for next Tuesday. I'll definitely have them do a thorough check of the wiring harness, including those connection points you mentioned. Really appreciate the tip about making sure they check the entire length, might save me from having to go back a second time! I'll update this thread once I get it sorted out. Your experience has been super helpful in narrowing down what to look for. Thanks again for taking the time to share all this!