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Q: Pcv valve problem

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I have a 2002 ram 1500 4x4 4.7l, i changed the pcv valve and pcv tubes because im burning alot of oil, after i changed the parts i had a check engine light come on, evap medium leak, so i checked the lines again to make sure all were good, the pcv valve rattles at idle then stops when increase in RPM but then when back to an idle it does not rattle, if i rev it while the pcv valve is not rattling white smoke comes from the top of the motor, not sure where to look next.

My car has 335000 miles.
My car has an automatic transmission.

A: Hello. In most case a PCV valve should not...

Hello. In most case a PCV valve should not noticeably rattle, though that varies from engine to engine. If it appears to be rattling excessively that could signify that the PCV valve is not secured properly, that there is a vacuum leak, or that the internal spring is weak or broken, and that the valve needs to be replaced.. An excessively rattling PCV valve could cause an unstable idle, hesitation, and oil consumption. A code for the EVAP system will usually be a separate issue from that of the PCV valve. If the code came on after working on the PCV valve, I would carefully check to see if there are any vacuum hoses or emissions hardlines that run near the PCV valve to see if they may be damaged or broken. If not, it may be possible that the EVAP leak is elsewhere. I would recommend having a professional technician, such as one from YourMechanic, come to your location to determine the cause of the PCV valve rattling, and if it may be related to the trouble code.

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