My car suddenly had problems accelerating and changing gears. Then my check engine light came on and it had a hard time starting. I've had a little knock in my engine for a little while, but no other issues. I took it to the shop and my mechanic checked it and said it was my Crankshaft Sensor. He got a new one from the Hyundai dealer and replaced it. However then it wouldn't start at all, so he got another one from somewhere else. Tried again, and still no start. Each time he would put the old one back in and it would eventually start. He thinks it's a major engine problem from the knock. The guy he asked at the dealer had never heard of such a problem. I'm at a loss for ideas and really don't want to buy a new car right now. Any ideas would be greatly appreciated.

 

What was the code in the computer that made the check engine light come on?

 

My mechanic tells me the code he got was PO335. Hope that helps.

 

CKP sensor is damaged open or shorted.
CKPsensor positive + circuit or _ circuit is open or shorted to ground.
CKP sensor is physicallt damaged ot it is improperly installed.
Ckp sensor is failed.
Electromagnetic interferrence EMI in the CKP circuits.
Excessive air gap between the CKP sensor and relucter ring.
Foreign material lodged between CKP sensor and relector ring.
ECM has failed try cleaning connections.
The knock can be bad bearings.

 

so I'm having the exact same problem did you ever figure out a solution?