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Off the water pump
I have a 98 GT it was underneath yhe car just follow the water hose
how to check fuse for horn in a 1998 Pontiac sunfire
The horn is located under the passenger side headlamp assembly.
In the area in front of the right front wheel below the headlight.
Try back near the fuel tank. if it is the same as my sunfire it is right behind the gas tank.
Behind the vibration dampner pully Wrong On a Pontiac sunfire 1998 with the 2.4L it's on the front of the engine tucked aboue the oil filter the bolt is a 5/32 size and it's hard to see
On the oil pan near the top. Under the engine. About middle of the car.
The filter is located inside the transmission just inside the bottom pan.
The PCM is located in the right corner of the engine compartment under the air cleaner assembly and bolted to the chassis.
See stvndberryhill's answer under 1998 Pontiac Sunfire horn relays. This answer applies to all year models of Pontiac Sunfires.