How to Replace a 1998 Buick Regal Oxygen Sensor

• 1). Park the Buick Regal on a level paved or concrete surface. Apply the parking brake.
  
  
• 2). Place a wheel chock behind one of the rear wheels.
  
  
• 3). Lift one front quarter of the Regal with the floor jack and place a jack stand under the front frame rail on that side. Repeat the procedure for the other side to elevate the front axle of the regal.
  
  
• 4). Put on safety glasses. Collect all the needed tools and crawl under the front of the Regal on a creeper if you have one.
  
  
• 5). Locate the oxygen sensor you wish to replace. One is located on the front exhaust pipe before the manifold in front of the catalytic converter, also known as upstream. The other is located behind the converter or in the shell of the converter, also known as downstream.
  
  
• 6). Spray a liberal amount of WD-40 on the threads of the oxygen sensor and let it soak in.
  
  
• 7). Locate the wire plug and connector. Unplug the oxygen sensor wire, using the screwdriver to help you push in the lock tab on the plug.
  
  
• 8). Slide the wire through the slot of the oxygen sensor socket on the ratchet (a proper sized box end hand wrench could work as well) and unscrew the oxygen sensor from the pipe. If it is rusted, you may have to apply heat to the pipe area around the sensor using a torch. Only apply heat to the pipe and not the threads of the sensor. If you used the torch to remove the sensor, take a break and allow the pipe to cool down.
  
  
• 9). Apply a light coat of anti-seize lubricant to the threads of the new oxygen sensor. Quality aftermarket sensors may already have a light coating on them.
  
  
• 10
  
  Screw the sensor into the pipe and tighten with the socket and ratchet. Tighten properly and snug, but understand there's only four or five threads on the sensor so you do not want to strip the threads by overtightening.
  
  
• 11
  
  Plug the oxygen sensor outlet into the wire plug.
  
  
• 12
  
  Remove the tools and lower the Regal. Remove the wheel chock.