Lexus IS Diesel Manifold Pressure Sensor Issue

Sounds familiar. I had similar symptoms on my old Renault Megane. It turned out to be a faulty MAP sensor. Is the engine idling rough?

Yeah, the idle's a bit rough sometimes. Was the MAP sensor the only thing causing your issues? Did you try anything else before replacing it?

MAP sensor was the culprit. I just took it to a workshop. They ran diagnostics and confirmed it quickly.

I took it to a shop and got it checked out. It was indeed the manifold pressure sensor and a large vacuum leakage as suspected. Cost me 235€ including sensor replacement. Runs like new!