The third-generation Nissan Altima arrived in the 2002 model year boasting larger dimensions all the way around, which jumped it into the midsize classification. This growth meant that the Altima also needed some extra power, which came via the model’s first-ever V-6 engine and a 175-horsepower, 2.5-liter four-cylinder. The base 2.5-liter engine in the 2006 Altima used a crankshaft position sensor to help the powertrain control module determine ignition timing, engine rpm and presence of a misfires. Replacing the crankshaft position sensor is not a tough task, but finding it is a different story if you don’t know where to look.
Open the hood and look on the passenger side of the engine block near the rear of the engine, and find the crankshaft position sensor – a small electrical component secured to the block by a single bolt. Press and hold the unlocking button on the crankshaft position sensor wiring harness, and unplug the harness from the sensor.
Remove the bolt that secures the crankshaft position sensor to the block, using a ratchet and socket, and pull the sensor from the block.
Roll the new O-ring – included with the new senor – up the engine side of the senor until it seats in the cutout near the flange on the sensor. Apply a thin coat of new engine oil to the O-ring with your finger and insert the crankshaft position sensor into the engine block.
Tighten the crankshaft position sensor bolt to between 48 and 64 inch-pounds, using an inch-pound torque wrench and socket. Plug the wiring harness into the crankshaft position sensor and close the hood.
