V90 Manifold Pressure Sensor Vacuum Leak

Hey, something similar happened with my old Saab 9-3. Check engine light, felt like I was driving with half the cylinders, and the gas mileage tanked. It was a vacuum leak messing with the intake manifold pressure sensor. Like trying to run a marathon with a clogged nose – the engine just couldn't breathe right. Check all your hoses and connections around the intake manifold; that's where they often crack.

Thanks. When you say 'vacuum leak,' what specific components should I check? Besides a visual inspection, are there other diagnostic procedures you'd recommend to find the leak?

Yeah, start with a visual, looking for cracks or loose connections. Those vacuum lines get brittle over time. I once tried spraying a tiny bit of starter fluid near the hoses to listen for the engine to rev up, which would mean a leak sucking in the fluid. But unless you're really comfortable with engines, I'd suggest a smoke test at a workshop. They pump smoke into the system, and you can easily see where it's escaping.

Thanks for the clarification and the smoke test idea. I took it to a workshop. The diagnosis matched my initial thought: a faulty manifold pressure sensor made worse by a vacuum leak. The repair, including parts and labor, was 235€.