It seems like you've already taken a step by replacing the electronic throttle body, addressing the previous stalling issue. However, the fluctuating RPM and the recent engine cut-out indicate there may still be underlying issues.

  1. [COLOR=var(--tw-prose-bold)]Idle Air Control (IAC) Valve:[/COLOR] Even though your car has an electronic throttle body, it might have an integrated IAC function. Check for any clogs or malfunctions in the IAC valve that could be causing the erratic idle.
  2. [COLOR=var(--tw-prose-bold)]Vacuum Leaks:[/COLOR] Inspect for vacuum leaks in the intake system, as they can lead to inconsistent idle and stalling. Check hoses, gaskets, and connections for any signs of wear or damage.
  3. [COLOR=var(--tw-prose-bold)]Throttle Position Sensor (TPS):[/COLOR] Even with the new throttle body, the TPS could still be a culprit. Ensure it's properly calibrated and functioning to maintain stable RPM.
  4. [COLOR=var(--tw-prose-bold)]Mass Airflow Sensor (MAF):[/COLOR] A faulty MAF sensor can contribute to irregular idling. Clean or replace it if necessary.
  5. [COLOR=var(--tw-prose-bold)]Fuel System:[/COLOR] Check the fuel system for issues such as a clogged fuel filter or a failing fuel pump, as they can affect engine performance.
  6. [COLOR=var(--tw-prose-bold)]Engine Control Module (ECM):[/COLOR] A malfunctioning ECM could lead to various issues. Consider having it checked or reprogrammed if needed.

If problems persist, it's advisable to consult a professional mechanic or use diagnostic tools to pinpoint the exact cause. Addressing these potential issues should help stabilize your car's idle and prevent stalling.