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RIP, Lead Technician
Category: Car
Satisfied Customers: 5591
Experience:  A.S.E. Master Technician, Advanced Level, Smog - European, Domestic, & Asian -- Car Category Mentor
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2002 Hyundai Sonata: camshaft..coil packs..rough idle and stalling

Resolved Question:

2002 Hyundai Sonata: Error Code PO340 have changed timming belt, camshaft pos sensor, plugs, wires, coil packs. still having problems with rough idle and stalling out after it gets warmed up.
Submitted: 10 years ago.
Category: Car
Expert:  RIP replied 10 years ago.

Hi, welcome to jA.

  • How many miles are on this Sonata?
  • Did the code appear after the timming belt was replaced?


Customer: replied 10 years ago.
Reply to RIP's Post: 105,000 miles
and the code appeared before and after the timing belt was replaced.
Expert:  RIP replied 10 years ago.

Thanks, XXXXX XXXXX code is set due to a failed Cam Sensor - which you have already replaced. If the timming belt was off, even slightly, after it was replaced; than it would've been the cause. Since those two possibilities have been ellimianted, you may have a PCM (powertrain control module) failure, or the wiring to the PCM, from the sensor. You'll need to first verify the wires are good from the sensot to the computer by disconnecting the sensor and using an ohm meter to measure good continuity of each wire to the PCM's side. Also inspect the wires at the Cam Sensor connnector and harness. If the wires have rubbed through on any metal nearby, it'll cause the signal to short as well. if the wiring checks are good than the problem must lie in the PCM, and that is further issoalted with a factory level scan tool, where you can monitor the Cam Sensor data.


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