What is the meaning that Timing valve is open? A local mechanic told me to change the timing valve to fix P0018 code. But he is not sure if there are othern hidden issues. Is it possible that Timing valve is open due to a stretched timing chain?

  • p0018 is a cam crank correlation code. it could be cam timing is off or that a cam phasor/actuator is stuck. what's the car/engine etc...? – Ben Sep 27 '16 at 13:31
  • sorry for my late reply. It is hyundai sonata 3.3L engine. – precision Sep 28 '16 at 2:55
  • Are you sure that the valve is open and not the crank position circuit is open (i.e. open circuit)? I take it that the car does not run in the state it's currently in? – Steve Matthews Sep 28 '16 at 10:35
  • The car runs but it shakes badly at idle when in drive mode. When the car is in neutral mode, shaking stops or reduces significantly. – precision Sep 28 '16 at 15:11

The P0018 code is related to your cam and crank showing incorrect timing

There are two sensors involved in this error.

  • Cam Position Sensor

  • Crank Position Sensor

These two sensors detect the angle of rotation of each shaft and when they fall out of tolerance in timing, you get this error.

There are multiple reasons why your crank and your cam(s) may be out of time.

  • Timing chain/belt has stretched beyond service limits and has taken the two shafts out of time due the amount of stretch the timing chain/belt has undergone over time.

  • Your timing chain/belt has skipped a gear tooth or cog taking the cam and crank out of synchronization

  • A bad cam or crank sensor or the wiring to either sensor


Some of the symptoms of an engine that has a legitimate timing issue between the crank and the cam.

  • Runs very rough

  • Only runs at certain RPM's

  • Doesn't run or start at all

  • Would you suggest OP to take the car to a different mechanic? If so, it will help to make this clear in the answer. – rana Sep 27 '16 at 20:27
  • @rana I think whether or not the OP wants to DIY the fix or take it to another mechanic is up to the OP. I do not know the OP's skill level and don't want to assume the OP wants to goto a mechanic or otherwise. I believe that decision is subjective and out of my realm. IF the OP would like to ask a question on how to time the engine or test a sensor, that might be the next step for them. OR.....they goto another mechanic. The original mechanic did indicate a timing issue. – DucatiKiller Sep 27 '16 at 20:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.