HomeTrouble CodesP2073

P2073 — Manifold Absolute Pressuremass Air Flow Throttle Position Correlation Idle

Manufacturer-specificPowertrain (engine & transmission)

The ECM monitors the relationship between throttle plate position and intake manifold pressure (or mass airflow) when the engine is idling. This code sets when the manifold pressure is lower than expected (higher vacuum) or airflow readings do not align with the nearly closed throttle position, indicating unmetered air is entering the intake or a sensor is reporting incorrectly.

Symptoms

What causes it — most likely first

1. Vacuum leak (unmetered air)

Intake manifold gasket, vacuum hoses, or PCV valve leaks allow air to enter after the throttle body, causing high vacuum readings that conflict with the closed throttle position.

2. Carboned or sticking throttle body

Excessive carbon buildup prevents the throttle plate from reaching its true closed position or disrupts airflow patterns, creating a mismatch between TPS signal and actual airflow.

3. Faulty MAP sensor

A sensor reading incorrectly high vacuum (low pressure) or stuck at a fixed value when the throttle is closed triggers the correlation error.

4. Faulty Throttle Position Sensor

Incorrect voltage output or dead spots in the sensor's range cause the ECM to see throttle angle data that does not align with actual airflow measurements.

5. PCV system malfunction

A stuck open PCV valve or disconnected hose creates a large vacuum leak downstream of the throttle plate.

6. Engine control module failure

Rarely, internal ECM processing errors cause misinterpretation of correct sensor signals; this should only be considered after mechanical and sensor causes are ruled out.

How it's diagnosed

  1. Visual inspection of intake hoses and vacuum lines for cracks, disconnections, or hissing sounds indicating unmetered air entry
  2. Smoke test the intake system to identify small leaks at the manifold gasket, throttle body gasket, or PCV connections
  3. Scan tool live data analysis comparing throttle position percentage, manifold absolute pressure (or grams/second on MAF-equipped vehicles), and calculated load at idle
  4. Throttle body inspection and cleaning to verify the plate seats properly and moves freely without carbon interference
  5. Sensor validation testing including MAP sensor voltage/pressure response to vacuum changes and TPS sweep testing for dead spots or erratic voltage jumps

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationManufacturer-specific (P1/B1/C1/U1)

Frequently asked

Can I continue driving with this code?

Short trips are possible, but the engine may stall at idle unexpectedly, creating a safety hazard in traffic; diagnosis should be performed promptly.

Do I need to replace my throttle body or will cleaning fix it?

Carbon buildup causing sticking is often resolved by thorough cleaning; only replace the throttle body if the plate is physically damaged, the motor (on electronic throttle) fails testing, or cleaning does not restore proper correlation.

My mechanic says I need a new engine computer. Is that correct?

PCM failure causing this specific code is extremely rare; insist on verification of vacuum integrity, throttle condition, and sensor accuracy before considering module replacement, as the issue is almost always mechanical or sensor-related.

Why does this happen specifically at idle?

At idle the throttle plate is nearly closed, making the expected manifold vacuum highly predictable; even small leaks or sensor errors create noticeable deviations that the ECM detects as correlation faults.