With a redesigned exterior introduced the year before, the 1997 Pontiac Grand Am had a sleek, aerodynamic body, which gave it a sporty look to go along with the peppy twin-cam, 2.4-liter, inline four-cylinder engine that came standard. The suspension gave it a decently smooth ride, but with a bit too much body lean around corners, the car's handling didn't match its sporty looks. If the oil pressure warning light on the dash illuminates, the cause may be a faulty oil pressure sensor. The sensor may also leak oil when it goes bad, since it is under pressure when the engine is running.
If you have fresh oil in the engine, you can reuse it, but this might be a good time to go ahead and change the oil and filter.
Park the car on level, unyielding ground. Set the emergency brake and chock the rear wheels. Open the hood.
Locate the front jacking notches 18 inches behind one front wheel well. Position the jack so that the cradle mates securely with the notch in the frame then lift the front of the car and support it on a jack stand. Repeat for the other side, so both sides are supported.
Position a clean drain pan beneath the engine oil drain plug. Clean the pan around the plug thoroughly if you intend to reuse the oil. Remove the drain plug, using a wrench, and drain all the oil from the engine. Discard the old oil pan drain plug gasket.
Find the oil pressure sensor right above the oil filter. Disconnect the electrical connector from the sensor. Wipe around the sensor with a shop rag to remove dirt or debris that may fall into the sensor hole. Remove the old sensor, using a ratchet and oil pressure sensor socket.
Apply a coat of thread sealer to the first few threads of the new sensor. Use caution to avoid getting any of the sealer in the open end of the sensor. Install the new sensor, tighten it hand-tight and then snug it with the ratchet and socket. Install the sensor electrical connector.
Install a new drain plug gasket on the engine oil drain plug, then install the drain plug and tighten it securely. Pour the oil back into the engine, then check for leaks around the drain plug.
Remove the jack stands and lower the vehicle to the ground. Test-start the engine, and ensure that the oil pressure indicator registers pressure. Check for leaks around the oil pressure sensor. Turn the engine off. Check and add oil as necessary to maintain the proper oil level.
