Discovery Diesel: Black Smoke & Power Loss Symptoms

Hey there! I've got some experience working on cars (medium level DIYer). Had a similar issue with my 2017 Range Rover Sport diesel last year. Those symptoms sound super familiar, I went through exactly the same headache! For me, it turned out to be faulty cable connections to several sensors. The connections had corroded and weren't giving proper readings. My mechanic found it during diagnosis, and it was causing similar issues, black smoke, power loss, the whole deal. Ended up costing me 155€ for the repair, including labor. The shop cleaned and replaced some connectors, and it's been running like a champ since then. But hey, could be different for your Discovery, these symptoms can have multiple causes. could you share: Any diagnostic codes you're getting? When did these symptoms first start? Has there been any recent work done on the vehicle? Does it happen more when the engine's cold or warm? This info would help nail down if it's the same issue I had or something else. Let me know!

Thanks for the detailed response! Mine's also at 80453 KM, just had its service last month. Those symptoms started right after a really long highway drive. The diagnostic shows P0087 (Fuel Rail/System Pressure Too Low) and P0191 (Fuel Rail Pressure Sensor Circuit Range/Performance). The issues are definitely worse when the engine's cold, and it takes forever to warm up properly now. Haven't had any recent work done besides regular maintenance. I'll definitely get those sensor connections checked out, that's a much cheaper fix than I was worried about! Did your mechanic need any special tools for the repair? Just trying to figure out if I should take it to the dealer or if my regular shop can handle it.

Hey again! Yeah, looking at those codes and comparing them to what I experienced, your situation sounds even more similar to what I went through with my Range Rover Sport. When I got those exact same codes, my regular mechanic was able to handle it just fine, no special tools needed beyond what a well-equipped shop would have. The diagnostic scanner was probably the most specialized thing they used. The cold start issues you're describing are spot on with what I experienced too. Mine would take ages to warm up, especially on chilly mornings. The highway drive thing is interesting, that's actually when my issues started becoming really noticeable too. The heat probably stressed those already weak connections. Just to share my full experience, my mechanic first checked the fuel pressure sensor itself because that's what the codes pointed to, but found the connections were the real culprit. They ended up cleaning all the sensor connections in the fuel system and replaced a couple of corroded connectors. The whole job took about 2 hours. Your regular shop should definitely be able to handle this. Just make sure they're comfortable working with diesel engines. Trust me, once they sort those connections out, you'll notice the difference immediately, my fuel economy went back to normal within one tank. Keep us posted on what they find! I'm really curious to see if it's the same issue.

That's super helpful to know it's probably not as bad as I feared! You're right, the symptoms are incredibly similar to what you experienced. My regular mechanic is pretty good with diesels, so I'll get it booked in with them rather than paying dealer prices. It's actually really reassuring to hear yours started acting up after a long drive too. I was worried I'd somehow damaged something major, but if it's just dodgy connections, that makes total sense. Two hours labor and some new connectors sounds way better than what I was imagining! I'll definitely update once it's fixed. Really appreciate you taking the time to share your experience, it's saved me a lot of worry (and probably money too!). Going to call my mechanic first thing tomorrow and get this sorted. Thanks again for all the detailed info!