Hello,
I bought Vectra C with engine issue (Z22YH). On idle it runned on two or three cylinders (sometimes cyl2 misfire, sometimes cyl4 misfire). It had no power when accelerator was pushed quick.
Desired pressure at idle should be 5000kPa and i had only 3000kPa
https://www.youtube.com/watch?v=D2ZCPvMwoLE
Ignition coil spark test is OK.
So I pulled out pressure regulator and drilled out filter on its tip. Now pressure at idle is OK (5000kPa) and engine runs at all four cylinders. When I push accelerator slow, engine can go to rew limitter. It can run fast and pressure is 10000kPa. But if I push accelerator quick, pressure drops to 3000kPa and engine is choking. After that, op-com reads error P1191-52.
Is it high pressure pump faulty or only blocked fuel filter?
I hope you can understand me 🙂