IS 200 Lean/Misfire codes

[Kostiks]

Hello everyone! I have issues with my lexus is 200 (1999, 1G-FE), the engine vibrates under acceleration, has misfire in cylinders  number 1,2,4 and feels like it's in LIMP mode . Stored DTCs- Lean mixture bank 1, misfires in multiple cylinders. Car runs fine and has power after reseting ECU for first 5minutes then Engine and TRC lights starts to flash and it looses power. I've tried to clean throttle body, checked fuel pressure, checked injectors- cleaned them, replaced both o-rings, tried to swap their places but still shows misfire in cylinder 1,2,4. Tried to switch coil pack positions but nothing changed( Their body is cracked), checked PCV valve, checked all vacuum lines, tried to block vacuum line from brake vacuum booster and block it but the problem is still there, I've no idea what should I do next.

[lexus22]

Have you plugged in an OBR reader to see what codes are stored? I assume the engine management light is on

[Kostiks]

51 minutes ago, lexus22 said:

Have you plugged in an OBR reader to see what codes are stored? I assume the engine management light is on

yes, P0174, P0301, P0302, P0304 also forgot to mention that I checked compression of all cylinders

[Mihanicos]

Most likely you have a failed lamda sensor on the up stream.

You need a scanner that can display the waveform of the short and long term fuel sensors. The upstream responds instantly and the median value of the waveform sets the downstream fuel trim sensor.  If the downstream fuel trim exceeds 20% correction of the stoichiometric value, then the engine computer sets the respective code.

Chris.