P2018: Intake Manifold Runner Position Sensor/Switch Circuit Intermittent Bank 1
What to do
Occasional brief flat spots that come and go are characteristic. Mention whether they relate to engine temperature or rough surfaces — both point at a connection rather than the sensor itself.
What this code means
The flap position signal on bank 1 drops out or jumps briefly. Because the module compares commanded position against reported, a momentary bad reading looks like a flap that moved when it should not have, and the module may respond by restricting power for a moment.
The result is intermittent flat spots with no obvious pattern — a car that occasionally feels dull for a few seconds and then recovers. Heat and vibration are the usual triggers, which points at the connector rather than the sensor.
Likely causes
Start here
- Corroded or loose connector · easy
- Damaged wiring harness · moderate
- Faulty manifold runner position sensor · moderate
Less common
- Broken manifold runner linkage · moderate
Symptoms
Components involved
Information, not instruction
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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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