P0068: MAP/MAF - Throttle Position Correlation
The P0068 code indicates a correlation issue between the Mass Air Flow (MAF) or Manifold Absolute Pressure (MAP) sensor and the Throttle Position Sensor (TPS). The Powertrain Control Module (PCM) detects that the airflow reading does not match the throttle position, often due to a dirty MAF sensor, vacuum leaks, or a faulty TPS. This can cause drivability problems and trigger the Check Engine Light.
1. Most Common Causes
- Faulty or contaminated MAP sensor
- Dirty or defective MAF sensor
- Misadjusted or damaged throttle position sensor
- Vacuum leak in the intake system
- Restriction in the intake air system
- Corroded, damaged, or shorted wiring or connectors
- Mechanical issue with the throttle body (carbon buildup, worn shaft)
- Clogged or faulty PCV valve airflow control
- Outdated software or internal failure in the ECM/PCM
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine hesitation or stumbling on acceleration
- Rough idle or stalling
- Reduced fuel economy
- Poor engine performance
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Inspect air intake system for vacuum leaks.
Step 3: Clean MAF sensor with approved cleaner.
Step 4: Test TPS voltage and compare to throttle angle.
Step 5: Check wiring and connectors for damage or corrosion.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause poor performance and potential damage to the engine or catalytic converter.
How much does it cost to fix?▼
Costs vary from $50 for cleaning the MAF sensor to $150 for replacing a faulty TPS or repairing vacuum leaks.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.