P0068: Manifold Absolute Pressure/Mass Air Flow — Throttle Position Correlation
Do not keep driving
Have it looked at promptly. A large air leak upsets fuelling across the whole range, and a throttle body that disagrees with its sensors can trigger a limp mode without warning.
What this code means
The module cross-checks three things that should agree: how far the throttle is open, how much air the mass air flow sensor reports, and what the manifold pressure sensor reads. This code means they do not agree, and the most common physical cause is a large unmetered air leak — a split intake boot, a disconnected hose, or a leaking manifold gasket letting air in downstream of the meter. It is a plausibility check rather than a component test, so it points at the system, not at a single part.
Likely causes
Start here
Less common
- Carbon deposits in the throttle body · easy
- Faulty throttle position sensor · moderate
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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