V40 Cylinder Pressure Fluctuations

Wow, that sounds eerily familiar! I own a V40, and I experienced almost the exact same symptoms a while back: increased fuel consumption, noticeable power loss, and that infernal check engine light illuminating my dash like a Christmas tree. Did you recently have the timing belt changed? I would also check the camshaft position sensor if I were you.

You're kidding! Seriously? That's oddly comforting and concerning at the same time. My timing belt is original, as far as I know. So, what exactly was the culprit in your case, and how much did it set you back? Was it a complicated fix, or something relatively straightforward?

Well, prepare yourself. In my case, it turned out to be a consequential error stemming from a seemingly unrelated issue. The garage told me the fluctuation was because of another sensor that was throwing the system's reading off. Honestly, I'd strongly advise getting it professionally diagnosed. Chasing ghosts under the hood without the proper diagnostic tools can be a costly and frustrating exercise. It sounds too similar to what I experienced, and you really don't want to risk doing more damage.

Okay, you've convinced me. It's going to the workshop. I was just hoping to avoid that. Turns out there was some dirt on one of the sensors which was causing a misreading and consequential errors that caused the cylinder pressure fluctuation. The mechanic removed the dirt and reset the ECU. The repair was completely free, thankfully!