06 4 cylinder auto, the ring that flags the crank position sensor has fallen off and is spinning freely. I've never had this car running, previous owner said it cut off while he was driving. Is this something I have to pull the engine for, or can it be repaired from the bottom through the oil pan? I can't find much info on google because the sensor is a much more common issue, but mine had the front sheared off by the ring.

 

Most of the time, you would need to place the vehicle on jack stands and remove the RF wheel. Then remove the plastic inner fender to gain access to the crank pulley.
Once the bolt securing the pulley to the crankshaft is removed you can remove the belt and the crank pulley is removed ,you should see the timing disc dangling around there. You must get a new one from a dealer, bring VIN , install it and a new crank sensor . Then temporarily install the disc and crank sensor assy. make sure the wiring is intact.. Once you are sure the gap between the sensor and disc are right .,you can install the pulley.and complete the reverse of removal.

 

Can you give me a little more detail? The ring is inside the engine, and the crank position sensor is right next to the transmission. Its nowhere near the accessory drive.


I've circled the location in green

 

I have never had to replace a crankshaft reluctor that was installed on the internal part of the engine.
From the info I have double checked it is supposed to be on the front of the engine.
You could always check with a HYundai dealership service dept or parts dept and they should be better able to answer your questions.