Worn or dirty throttle position sensor tracks or internal contacts causing an intermittent voltage drop.; Chafed, cracked, or heat-damaged wiring in the sensor signal or reference circuit, often near the throttle body or harness bend.; Loose, corroded, or backed-out terminals at the throttle position sensor connector or the engine computer connector.; Water or oil intrusion into the sensor connector or throttle body area causing intermittent contact.; A failing throttle body assembly on electronic throttle vehicles, where the sensor is integrated and not separately serviceable.; Poor engine ground or reference voltage supply that momentarily shifts the sensor signal.; Less commonly, a failing engine computer driver circuit for the sensor reference or signal line.

DTC codes / P01xx · Fuel and air metering / P0124

P0124Throttle Position Sensor A Circuit Intermittent

Q: What does code P0124 mean?

Throttle Position Sensor A Circuit Intermittent. P0124 means the engine computer has detected an intermittent fault in the signal circuit for throttle position sensor A, which is the primary sensor that reports how far the throttle plate is open. The computer sees the sensor voltage drop out, spike, or jump erratically for brief moments rather than failing completely, so the fault is logged as intermittent rather than a hard circuit failure.

P0124 means the engine computer has detected an intermittent fault in the signal circuit for throttle position sensor A, which is the primary sensor that reports how far the throttle plate is open. The computer sees the sensor voltage drop out, spike, or jump erratically for brief moments rather than failing completely, so the fault is logged as intermittent rather than a hard circuit failure.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering

Symptoms you may notice

The check engine light may be the only thing you notice, especially if the glitch is brief and the computer can still estimate throttle position.
A momentary stumble, hesitation, or surge when accelerating gently or holding a steady speed.
Brief erratic engine idle or a flare in rpm that corrects itself almost immediately.
Occasional delayed or harsh automatic transmission shifts because shift scheduling relies on throttle position.
In some vehicles, reduced power or a limp-home mode if the intermittent signal is frequent enough to be judged unreliable.

Common causes, most likely first

Worn or dirty throttle position sensor tracks or internal contacts causing an intermittent voltage drop.
Chafed, cracked, or heat-damaged wiring in the sensor signal or reference circuit, often near the throttle body or harness bend.
Loose, corroded, or backed-out terminals at the throttle position sensor connector or the engine computer connector.
Water or oil intrusion into the sensor connector or throttle body area causing intermittent contact.
A failing throttle body assembly on electronic throttle vehicles, where the sensor is integrated and not separately serviceable.
Poor engine ground or reference voltage supply that momentarily shifts the sensor signal.
Less commonly, a failing engine computer driver circuit for the sensor reference or signal line.

How to diagnose and fix it

Scan all modules and record freeze-frame data for P0124, then clear the code and test-drive to confirm whether it returns and under what conditions.
Inspect the throttle position sensor connector and harness for corrosion, loose terminals, chafing, and heat damage, and wiggle-test the harness while watching live sensor voltage.
Backprobe the sensor signal, reference, and ground wires and compare live voltage to the scan tool reading through the full throttle sweep to spot dropouts.
Clean the throttle body and sensor mounting area if contamination is present, then recheck the live data for smooth voltage transition.
Replace the throttle position sensor or integrated throttle body only after electrical testing confirms the sensor itself is dropping out.
Repair or replace damaged wiring and terminals, then verify with a road test that the intermittent signal is gone and the monitor completes.
Perform a throttle relearn or idle relearn if the vehicle requires it after sensor or throttle body service, then confirm no pending codes return.

Why intermittent throttle codes fool parts changers

An intermittent code often leaves no current fault when you scan, so the live data looks perfect on a stationary engine and the real dropout only appears during vibration or heat cycling on the road.
A worn sensor track can test fine at idle and at wide-open throttle but drop out at one small throttle angle, so a full slow sweep with a graphing scan tool matters more than a simple min-max voltage check.
Harness rub-through near the throttle body is a common missed cause, and the code may set only on bumps or engine movement rather than during steady driving.
On electronic throttle vehicles the throttle position sensor is often part of the throttle body assembly, so technicians who replace only the pedal sensor chase the wrong component.
A weak battery or poor ground can create brief reference voltage shifts that mimic a failing sensor, so check charging and grounds before condemning the sensor.

Can I keep driving with P0124?

You can usually drive the vehicle to a shop, but avoid aggressive acceleration and towing until the fault is diagnosed because an intermittent throttle signal can cause unexpected stumbles or reduced power. If the vehicle enters limp mode or the throttle response becomes unpredictable, stop driving and have it towed.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.