This is easy job, and very difficult at the same time. In general, you just remove the serpentine belt, remove the coil pack if located over the belt for wrench clearance, use a large (approx 15/16 inch I think) socket and breaker bar, remove center bolt, pull off the old balancer, and install new, torque to approx 135 foot-pounds. However..... the old bolt may be seriously overtightened from the factory, and restraining the old balancer from turning takes a HUGE strap wrench. The balancer bolt on my 87 Park Ave took approx 250-300 foot-pounds torque to loosen it. Wow. Forces here can be large, and serious injury can result. You might consider taking to a shop-- this job can get ugly.
On the harmonic balancer/driverside
They are on the harmonic balancer but are they on the drivers side or on the passenger side?
The crank sensor is located behind the Harmonic balancer. Try not to break the rubber within the Harmonic balancer when removing or on the safe side replace both the Crank sensor and the Harmonic balancer ( the big pulley on the bottom - most part of the engine.)
at the front of the engine,next to the harmonic balancer
Easiest way is with an air impact. There are strap clamps available that would go around the harmonic balancer that would hold it while the bolt was tightened.
If you look at the harmonic balance you will see on the front of it a medium size circle. That will be your timing mark.
The "Harmonic Balancer", is found under the hood, its the biggest pulley on the bottom of the engine, there are three drivebelts, one for the fan and waterpump, ac and alternator.
Normal right hand thread. Counter clock wise to loosen.
take off the right wheel and the cover wall and you wll see it
The Crankshaft sensor is located behind the Harmonic Balancer on the front-passenger side
Behind the harmonic balancer. You will need to remove the right front tire, remove the access panel to the engine (through the wheel well), remove engine belt, remove harmonic balancer & pulley with a puller. Remove & replace crank sensor, align sensor with an alignment tool, replace balancer with an installer tool.. BE VERY careful with the balancer, the backside of it has a hall effect style blades. bending these blades will junk the balancer.
== == I do believe if you hear a knocking noise that your crank shaft could be failing. Which means you will need a new engine. Have it checked out. Replace the harmonic balancer they will make a bad knocking noise. When you start it and the oil light goes out and it knocks, this is what is wrong with it.