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P0087 on Buick Encore GX

Fuel Rail/System Pressure - Too Low

Factory diagnostic protocol and troubleshooting wire for fault code P0087 specifically for the Buick Encore GX (2020–2026, 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)).

Verified OEM Telemetry & Field Repair Tree
Buick Encore GX2020–2026
Buick Encore GX
SUV1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Encore GX SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$150 - $1,200 (DIY: $80 - $350)
Parts & Labor DIY
Check P0087 On Another Buick Model:
Diagnose P0087 on Specific Encore GX Model Year:

1. Symptoms of P0087 on Buick Encore GX

When the Engine Control Module (ECM/PCM) on your Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)) logs fault code P0087, drivers commonly observe:

Check Engine Light illuminated on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Engine cranks but takes a long time to start (hard starting) on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Noticeable lack of engine power or acceleration hesitation on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Engine sputtering, surging, or dying under heavy throttle on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Accompanying misfire codes (P0300, P0301-P0306) on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Buick Encore GX OBD-II Port Location
The 16-pin diagnostic connector is located Under driver side lower dash near knee panel. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Buick Encore GX

Historical warranty claims and technical repair bulletins for Buick Encore GX point to the following failure distribution:

55%
Failing High-Pressure Fuel Pump (HPFP) (Buick OEM Part)
25%
Clogged fuel filter or restricted in-tank low-pressure fuel pump (LPFP) (Buick OEM Part)
12%
Faulty fuel rail pressure sensor (FRP) reading incorrectly (Buick OEM Part)
8%
Clogged or leaking fuel injector stuck open (Buick OEM Part)
8%
Faulty fuel pressure regulator or damaged fuel supply lines (Buick OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Buick Encore GX.

3. Step-by-Step DIY Repair Guide for Buick Encore GX

01
Scan Live Data for Desired vs Actual Fuel Rail Pressure

Connect an OBD-II scan tool and inspect live Mode $01 telemetry for Fuel Rail Pressure (FRP). Compare actual pressure against the ECU's desired setpoint during idle and 2,500 RPM revs. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: OBD-II Scanner with Live Data
02
Test In-Tank Low Pressure Supply

Verify the low-pressure lift pump is delivering 55–75 PSI to the HPFP using a mechanical fuel pressure gauge on the Schrader valve. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: Fuel Pressure Gauge Kit
03
Inspect Fuel Rail Pressure Sensor & Wiring

Check the 3-wire FRP sensor harness for 5V reference, ground, and signal voltage (typically 0.5V at key-on to 4.5V at peak pressure). on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: Digital Multimeter, Backprobe Pins
04
Replace High-Pressure Fuel Pump (HPFP) or Fuel Filter

If low-pressure feed is verified but rail pressure remains under threshold, replace the camshaft-driven HPFP and follower. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: Socket Set, Torx Bits, Fuel Line Disconnect Tool
05
Clear Codes and Perform Extended Drive Cycle

Clear DTC memory with scanner, start engine, check for fuel leaks, and drive for 15 minutes to verify fuel pressure monitors pass. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Buick Encore GX (P0087)

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Direct-Fit Replacement Part

Buick Encore GX OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Buick Encore GX.

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Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

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Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Buick Encore GXVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Buick Encore GX

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Buick Encore GX:

4. Buick Encore GX P0087 FAQs

What causes code P0087 to trigger on a Buick Encore GX?

On the Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)), P0087 is most frequently caused by Failing High-Pressure Fuel Pump (HPFP) or Clogged fuel filter or restricted in-tank low-pressure fuel pump (LPFP).

Where is the OBD-II port located on my Buick Encore GX?

On the Buick Encore GX, the 16-pin DLC diagnostic connector is located Under driver side lower dash near knee panel. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Buick Encore GX with code P0087?

No. Low fuel pressure causes severe engine hesitation, misfires, stalling at speed, and lean detonation. Given that P0087 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.