P0102 Code on a Buick: MAF Sensor Circuit Low Frequency (Buick Guide)

P0102 on a Buick is "Mass Air Flow (MAF) Sensor Circuit Low Frequency." Most people read "low" as "low voltage," but GM's MAF sensors on most Buicks send a frequency signal, and P0102 means that frequency dropped out of its plausible range. It is an electrical code — and GM's two Buick documents for it are refreshingly specific. On the 2013–2014 Enclave and LaCrosse V6, GM says the code is often set by someone unplugging the MAF with the key on. On the Encore GX, GM traced it to a zip tie pulled too tight on the sensor harness.

What Does P0102 Mean on a Buick?

The MAF sensor sits in the air intake between the air filter box and the throttle body and tells the ECM how much air the engine is drawing in. The ECM uses that number to calculate fuel. On most modern Buicks the MAF housing also contains the intake air temperature sensor and, on many, a humidity sensor and barometric pressure sensor — GM calls this a multifunction intake air sensor.

GM's wording for P0102 is MAF Sensor Circuit Low Frequency. GM's 2006 parameters for the 3.8L V6 describe it as detecting a "continuous short to low or open in either the signal circuit or the MAF sensor." GM's 2021 tables for the newer Continental MAF describe a continuous short to ground in the circuit, or a sensor outputting a frequency that is too low.

In plain terms: the signal wire is not carrying a usable signal. That is very different from P0101, the performance code, where the signal is present but disagrees with GM's airflow model.

A Frequency Code, Not a Voltage Code

GM MAF sensors on most Buicks produce a square-wave signal whose frequency changes with airflow. The ECM counts the pulses. If the signal wire is open, shorted to ground, or the sensor has no power, the ECM sees few or no pulses — and that reads as a low frequency.

One detail in GM's 2021 table is easy to miss: on that sensor, a low frequency corresponds to high airflow (the table pairs 1,050 Hz with 161.5 g/s or more). So on that Continental MAF, "low frequency" is not the same as "low airflow" — the ECM is seeing a signal that is out of its plausible range. GM's 3800 table brackets the signal from both sides — P0102 at or below 1,200 Hz and P0103 at or above 11,500 Hz. Either way, a dead signal sets P0102.

The power side matters too. GM's enable conditions require the supply voltage to be up; a blown fuse or failed relay feeding the MAF can leave the sensor dead and the code set.

Which Buicks Set P0102

Every MAF-equipped Buick can set P0102. GM's parameter tables list it for the 3800 V6 (Regal, LeSabre, Park Avenue, LaCrosse, Allure, Lucerne), the 3.6L V6 (LaCrosse, Regal, Enclave), the Ecotec four-cylinders and the turbo engines in the Encore, Encore GX and Envista.

GM documents name P0102 on two Buick groups:

• 2013–2014 Enclave and LaCrosse with the 3.6L (LLT/LFX) — PI1009, codes set by disconnecting the MAF sensor with the ignition on.
• 2020–2022 Encore GX, 1.2L and 1.3L — bulletin 22-NA-008 and engineering information PIE0682A, a broken wire in the multifunction sensor harness.

What GM's Bulletins Say

PI1009 — Enclave and LaCrosse V6 (2013–2014). The MAF on these engines is a multifunction sensor. GM's PI lists P0097 (IAT 2 low), P00F4 (humidity low), P0113 (IAT high), P2229 (baro high) and P0102 together, and says the condition "may be caused by disconnecting the mass air flow (MAF) sensor with the ignition key on and/or the engine running" while servicing the A/C fill port, the air filter or other underhood parts. GM's instruction is simple: recheck that the connector clicks fully into place and clear the codes.

The lesson applies to any Buick: if P0102 appeared right after an air filter change or other underhood work, look at that connector before anything else.

22-NA-008 — Encore GX (2020–2022). GM lists U060F, U1346, P0101, P0102, P1101 and P14B6 with a check engine light and a reduced power message. The cause is a possible broken wire in circuit 492 of the multifunction sensor: a zip tie at a harness retainer may be too tight, and the wire breaks there as the harness flexes on acceleration. The technician inspects the second retainer back from the MAF with the engine running, wiggles the harness to reproduce the fault, and repairs the circuit — GM recommends replacing all the wires in that section with the pigtail listed in the bulletin.

PIE0682A was GM's matching request for pictures of the broken wire, now closed; it confirms the issue covers both the 1.2L (LIH) and 1.3L (L3T).

Symptoms of P0102

• Check engine light — on the newer engines potentially on the first trip
• Rough running, hesitation or stalling as the ECM falls back on calculated airflow
• Reduced engine power message, named in GM's Encore GX bulletin
• Hard starting in some cases
• Companion codes for the other sensors in the same housing — P0097, P00F4, P0113, P2229 — when the connector or shared wiring is the cause
• Symptoms that come and go with engine movement if a wire is broken inside the insulation

Causes and How to Confirm Each

How Is P0102 Diagnosed?

1. Note every code. Several codes from the same multifunction sensor point at its connector, power or ground — not at the MAF element.
2. Ask what was done recently. An air filter change with the key on is GM's own documented cause on the 3.6L.
3. Reseat and inspect the connector. Make sure it latches.
4. Watch MAF data at idle. A reading that drops to zero or jumps with harness movement locates the fault.
5. Check the sensor's fuse, supply voltage and ground.
6. Test the signal circuit for open and short to ground back to the ECM, per the wiring diagram.
7. On an Encore GX, inspect the harness retainers behind the sensor per 22-NA-008.
8. Replace the sensor last, then clear the code and confirm on a road test.

Parts and Cost

Buick MAF sensors vary by engine and year — some include humidity and pressure sensing, some do not. Order against your VIN.

GM Documents That Name P0102 on Buicks

Have a dealer check your VIN against current bulletins and campaigns rather than relying on any article, including this one.

What Other P0102 Pages Get Wrong

• "Low airflow — check for a clogged filter." A dirty filter does not make a MAF signal disappear. P0102 is a circuit fault.
• "Clean the MAF sensor." Cleaning can help a performance code. It does not repair an open or shorted circuit.
• Calling it a voltage code. Most GM MAF sensors on Buicks report frequency; GM's wording is "Circuit Low Frequency."
• Replacing the sensor when several codes appear. P0102 with P0113, P0097 and P00F4 points at the shared connector or wiring.
• Missing the obvious. GM's own 3.6L document says the code often follows someone unplugging the MAF with the key on.

For the related performance code, see our P0101 MAF performance guide.

Frequently Asked Questions

Can I drive with P0102?

Usually, for a short distance. The ECM estimates airflow from other sensors, so the engine runs but may hesitate, stall or go into reduced power. Get it checked soon.

I just changed my air filter and now have P0102 — why?

The MAF connector was probably unplugged with the key on, or not fully latched afterwards. GM documents exactly this on the 3.6L Enclave and LaCrosse. Reseat it and clear the code.

Will cleaning the MAF fix P0102?

Rarely. P0102 means the signal itself is missing or out of range, which is almost always wiring, power, ground or the sensor's electronics.

Why are there other sensor codes with P0102?

On many Buicks the MAF housing also contains the intake air temperature, humidity and pressure sensors. A connector or shared wiring fault sets codes for all of them.

Is P0102 the same as P0101?

No. P0101 is MAF performance — the signal is present but disagrees with GM's model, often because of an air leak. P0102 means the circuit itself has failed low.

Could mice cause P0102?

Yes. The MAF harness runs right beside the airbox, a favorite spot for nesting. See our rodent wiring damage guide.