Discovery Power Loss: Stalling & Rough Idle Problems

Hi there! I've got some experience working on cars, though I wouldn't call myself an expert. I actually faced almost the exact same issue with my 2011 Range Rover Sport (also had a similar problem on a Defender). Those symptoms sound really familiar, my car was doing the rough idle, power loss, and terrible fuel economy too. Took it to my regular mechanic who diagnosed a faulty crankcase ventilation system. The repair involved replacing the valve and some related hoses that had deteriorated. Cost me about 360 Euro total, but it fixed all those issues completely. Engine's been running smooth since then. Before I share more specifics, could you tell me if you're getting any specific error codes? Also, have you noticed any oil consumption issues or white smoke from the exhaust? This info would help confirm if we're dealing with the same problem. Just a heads up, this isn't something I'd recommend fixing yourself unless you're really comfortable with engine work. It's a bit tricky to access everything properly.

Thanks for the detailed response! Yeah, I've got the same symptoms with my Discovery at 126623 KM. Haven't checked the error codes yet, but I'll grab my OBD reader tonight. No white smoke that I've noticed, but definitely burning more fuel than usual. Really helpful to know about your experience with the ventilation system, I'll get it checked out by my mechanic. This started right after my latest service actually, which is pretty annoying. Haven't seen any major oil issues yet, but I'm keeping an eye on it. Did yours take long to fix when you got it done?

Hey again! Yeah, it took my mechanic about 4-5 hours to fix my Range Rover Sport. Since you mentioned it started after your service, that's actually pretty similar to what happened with mine, started acting up about a week after routine maintenance. Really frustrating timing! Just to share my complete experience, the repair wasn't super quick because they had to remove quite a few components to access everything properly. The ventilation system is tucked away in a pretty awkward spot. My mechanic also found that some of the connecting hoses were pretty brittle, so they replaced those while they were in there. Good preventive maintenance, you know? About the fuel consumption, mine was drinking fuel like crazy before the fix. I was getting about 30% worse mileage than normal. After the repair, it went right back to normal. Since you're experiencing similar symptoms, I'd bet you're dealing with the same issue. Quick tip, when you check those error codes, look out for P0171 or P0174. Those were the ones I got, and they're pretty common with crankcase ventilation problems on these engines. Let me know what you find out with the OBD reader. I'm really curious if it's the same problem I had!

Thanks so much for all this info! Just checked the codes with my OBD reader and what do you know, got P0171 showing up! That's pretty much confirmed my suspicions. Really appreciate you mentioning the repair time too, helps me plan better knowing it'll be a 4-5 hour job. I'll definitely tell my mechanic about those brittle hoses you mentioned, might save some trouble down the line. Honestly, it's such a relief knowing someone else has dealt with this exact same issue and got it sorted. Was getting worried it might be something way more serious (and expensive!). I've already called my mechanic and booked it in for next week. Will definitely be keeping an eye on those fuel consumption numbers after the fix, hoping to see the same improvement you did. Thanks again for taking the time to share your experience. You've really helped me figure this one out!