Corolla Diesel Cylinder Pressure Fluctuations

Whoa, that sounds rough! I had a similar issue with my old Renault Megane, although it was a petrol engine. Same symptoms: higher fuel consumption and reduced engine power. For me, it turned out to be a faulty sensor messing with the air/fuel mixture. Think of it like a clogged artery - everything backs up! Have you had any diagnostics run to pinpoint the source of the fluctuation? Is it always happening or just under certain conditions?

Interesting about the sensor on your Megane. I did a basic OBD scan, and it's throwing a bunch of generic codes related to misfires and pressure imbalances. Nothing specific though. It seems worse under load, like going uphill or accelerating. Could a dodgy sensor really cause this much havoc in a diesel?

Yeah, a faulty sensor can definitely cause chaos, especially with modern engine management systems. It's like a domino effect, one small problem leading to bigger issues. Since the OBD scan isn't giving you a clear answer, I'd recommend taking it to a workshop for a proper diagnostic. They can usually pinpoint the exact cause with more advanced tools. It might save you a ton of time and money in the long run. Good luck!

Thanks for the advice! I went to the workshop like you said, and they ran some fancy tests. It turned out to be a faulty EGR valve causing all the pressure weirdness. Replaced it, and the car's running perfectly now. Cost me 0€ because the dealership repaired it for free!