Buick / Chevrolet 4-Pin GT Series Ignition Coil / Oxygen Sensor Connector – OEM 15326815 / 15487755
Direct OEM-specification replacement for the Delphi GT series 4-pin waterproof wire harness connector used on ignition coils and oxygen sensors across Buick and Chevrolet GM platforms. Cross-references Delphi / GM OEM part numbers 15326815 and 15487755. Uses the 1.5mm contact series in black nylon housing — the GT series is GM’s standard connector family for ignition coil and sensor circuits on LS, LT, and Ecotec engine platforms.
The 4-pin GT series connector is used on two critical engine management circuits on GM vehicles. As an ignition coil connector, it is located on the valve cover in a high-heat, high-vibration zone. A failed connector causes a cylinder misfire (P0300–P0308) and rough running. As an oxygen sensor connector, a failed connection causes P0130–P0167 fault codes, rich/lean running, and increased fuel consumption. The GT series locking tab is prone to fracturing on high-mileage vehicles, allowing the connector to work loose under vibration.
| OEM Number | Application |
|---|---|
| 15326815 | Delphi GT 4-pin connector (primary) |
| 15487755 | Delphi GT 4-pin connector (alternate / superseded) |
| Pin | Function | Failure Symptom if Open |
|---|---|---|
| 1 | Coil power supply (12V) | No spark, cylinder misfire P0300–P0308 |
| 2 | Coil ground | Coil inoperative |
| 3 | Ignition trigger signal from ECM | No spark, misfire |
| 4 | Coil feedback / diagnostic signal | Misfire detection fault |
| Attribute | Detail |
|---|---|
| Pin Count | 4-Pin |
| Contact Series | 1.5mm pitch (Delphi GT series) |
| Housing Material | Nylon, black |
| Sealing | Waterproof |
| OEM Part Numbers | 15326815 / 15487755 |
| Applications | Ignition coil, oxygen / lambda sensor |
| Compatible Models | Buick LaCrosse / Regal / Excelle; Chevrolet Cruze / Malibu / Trax / Equinox |
| Terminal Included | Yes |
Q: My Chevrolet Cruze has a P0301 misfire fault — could it be the ignition coil connector?
A: Yes. A loose or corroded 4-pin GT series ignition coil connector is a common cause of P0300–P0308 misfire faults on GM Ecotec engines. The locking tab fractures on high-mileage vehicles, allowing the connector to work loose under vibration. Swap the coil to another cylinder first — if the misfire follows the coil, replace the coil. If it stays on the same cylinder, inspect the connector and wiring.
Q: Are terminals included?
A: Yes, terminals are included with all variants.
Be the first to know about new collections and special offers.
4 Pin Connectors
