MazicBay Diagnostics
MAZICBAYDiagnostics
FTC Reader Disclosure: When you purchase or register through links on our site, we may earn an affiliate commission at no extra cost to you. Read our Editorial & Advertising Policy.

P0354 on Buick Encore GX

Ignition Coil D Primary/Secondary Circuit Malfunction

Factory diagnostic protocol and troubleshooting wire for fault code P0354 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
$100 - $350 (DIY: $30 - $90)
Parts & Labor DIY
Check P0354 On Another Buick Model:
Diagnose P0354 on Specific Encore GX Model Year:

1. Symptoms of P0354 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 P0354, drivers commonly observe:

Flashing CEL on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Rough running on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Loss of power on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
P0304 code 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%
Dead Cylinder 4 ignition coil (Buick OEM Part)
25%
Wiring damage (Buick OEM Part)
12%
Corroded connector (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
Test Coil with Swap Method

Swap Coil 4 to Cylinder 1. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: 10mm Socket
02
Replace Coil 4

Install new OEM coil pack. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: Socket Set
03
Clear DTCs

Clear memory and road test. 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 (P0354)

Prime Fast Delivery & Verified Fitment
OEM Ignition Component

Direct-Fit Laser Iridium Spark Plugs (Set of 4/6)

4.8 / 5.0 (Top Rated)

Pre-gapped iridium spark plugs engineered to restore smooth combustion on Buick Encore GX.

$36 – $68 Prime
Check Price on Amazon
Ignition Service Tool

Magnetic Swivel Spark Plug Socket Set

4.8 / 5.0 (Amazon Choice)

360-degree magnetic swivel socket prevents ceramic plug cracks inside deep engine spark wells.

$16.99 Prime
View on Amazon
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.
Find Parts on Amazon
* As an Amazon Associate, MazicBay earns from qualifying purchases. Prices & availability subject to change.

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 P0354 FAQs

What causes code P0354 to trigger on a Buick Encore GX?

On the Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)), P0354 is most frequently caused by Dead Cylinder 4 ignition coil or Wiring damage.

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 P0354?

No. Cylinder 4 ignition coil has failed. Given that P0354 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.