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?
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