S80 Jerking Acceleration

Hey, I had a similar problem with my S80 a while back. Jerking, rough running, and the check engine light were driving me nuts! Did you check for any hissing sounds around the intake manifold? That could be a sign of a gasket leak. Also, have you noticed any changes in your fuel economy? When mine went bad, I was getting awful mileage because the engine was misfiring like crazy. It felt like the engine was suffocating, especially at lower speeds. I'd definitely investigate that intake manifold, paying close attention to the manifold pressure. Could very well be your issue.

Thanks for the quick reply! No hissing sounds that I've noticed, but I'll definitely check again tomorrow. Fuel economy has been a bit worse than usual, yeah. When you say 'investigate the intake manifold,' what exactly did you do? Did you try any DIY fixes, or did you just take it straight to a mechanic?

Honestly, I'm not much of a mechanic myself. I took one look at the intake manifold, remembered a friend mentioning similar issues, and noped straight to the workshop. It turned out the intake manifold gasket was completely shot. The scorching was pretty obvious once they took it apart. Given your symptoms, it really does sound like the same issue. For me, it was the intake manifold leaking. If you're not comfortable tackling it yourself, I'd recommend getting a professional to have a look. It can save you a lot of headaches in the long run!

Thanks a lot for your advice. I was hoping it wouldn't come to this, but I think you're right. I'll book it in with a mechanic. I got a quote for around 1180€ for the repair. Hopefully, that'll sort it out. Thanks again!