Honda Accord Diesel: Power Loss & Hissing Sound Issue

Hey there! I've got some experience working on cars (not a pro, but I've dealt with my fair share of issues). Had a very similar problem with my 2015 Honda Civic Diesel last year. Those symptoms sound exactly like what I experienced, it was definitely a swirl flap issue in my case. Took it to my regular workshop and they confirmed the swirl flap had broken in the intake manifold. The repair set me back about 865 Euro, including parts and labor. They had to replace the entire assembly, but it fixed all those symptoms you described, the power loss, rough idle, everything. Before I can share more specific details, what's your mileage, and have you noticed any other warning lights besides the check engine light? Also, have you had any recent maintenance done? This info would help me give you more relevant advice based on my experience. Trust me, you'll want to get this checked out soon, if it is the swirl flap, driving with it broken could cause more expensive damage later on.

Thanks for sharing your experience! My Accord's at 67134 KM and just had its service last month. Good to hear you had a similar issue and got it fixed. That price doesn't sound too bad considering the work involved. I'll definitely get it checked soon, don't want to risk any further damage. The check engine light is the only warning showing up right now. Thanks for the heads up about potential damage, gonna call my mechanic first thing tomorrow.

Hey again! Thanks for the quick follow-up about your mileage and recent service. Yeah, that's actually pretty similar to when my issue popped up, I was around 71000 KM when it happened with my Civic. Just wanted to add something I forgot to mention in my first reply, before I got it fixed, I noticed the symptoms would get worse during cold starts, especially in the morning. Did you notice anything similar? Also, my fuel consumption went up by about 15% when this was happening. Since you mentioned you just had service last month, definitely tell your mechanic about that. In my case, the problem started showing up shortly after a routine service too. Turned out some carbon build-up had contributed to the swirl flap issue. The mechanic ended up doing a thorough intake cleaning along with the flap replacement, which helped prevent the problem from coming back. Quick tip from my experience, while you're waiting to get it into the shop, try to avoid aggressive acceleration. I found that driving it gently helped minimize the jerking and hissing until I could get it fixed. Let us know how it goes with the mechanic! Always curious to hear if others' experiences match up with what I went through.

From's perspective: Thanks so much for all the extra details! Actually, yes, now that you mention it, the symptoms are definitely worse during cold starts. I've been trying to warm up the engine a bit longer in the mornings because of this. Haven't tracked my fuel consumption closely, but the tank does seem to be emptying faster than usual. Really appreciate the tip about taking it easy on the acceleration, I'll definitely keep that in mind until I can get it looked at. It's actually reassuring to hear that your symptoms were so similar to mine, and that the fix resolved everything. The carbon build-up info is super helpful too, I'll make sure to mention both that and my recent service to the mechanic. I'll keep you posted on what they find. Thanks again for taking the time to share your experience in such detail, it's really helped me understand what might be going on with my car!