Repeated PCV Failure

[QuattroCan]

Two years ago I replaced my PCV valve and things were fine for 2 years. This past January I had my mechanic replace the PCV after experiencing P0171 and P0507. It has since failed 2 additional times approximately 2 weeks apart and has now failed for a third time since January. Currently CEL P0171

I have enjoyed this car but this is pushing me to trade it in. Are there any other conditions that could lead to this repeated failure?

08 A4 with 95,000 KM
APR STG 1

THANKS

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[Charles.waite]

Neither of those codes have much to do with the pcv. What makes you think it's failed?

[QuattroCan]

The infamous noise it makes (Whistle)

It has thrown both codes in conjunction with the whistle each time. Replace the PCV each time and it resolves for 2 weeks give or take then it retuns.

Also have a rough idle. Has started as a fluctuating idle and then after a couple of days it tends to just sit high (1300 Rpms) vs the norm which tends to be 780-820.



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[IKE20VA4]

Are you replacing with OEM? I replaced my OEM original one with 125,000 miles on it with non-OEM and turned out the non-OEM one had a hairline crack in the plastic that caused a "P0456 - 001 - Very Small Leak Detected - Intermittent". Put the original OEM one back one and I'm good to go. 3rd time I've been burned by non-OEM plastic parts for these cars.

[mtroxel]

I replaced my OEM original one with 125,000 miles on it with non-OEM and turned out the non-OEM one had a hairline crack in the plastic that caused a "P0456 - 001 - Very Small Leak Detected - Intermittent".

Similar story here. My Vaico PCV lasted 11 months.

[_muppet_]

I bought an aftermarket one from a vendor on here that was bad right out of the box. I swapped it because I had oil seep around the valve cover, the next day going up a hill I had a huge cloud of smoke behind the car. I pulled the pcv and it wasn't holding any pressure at all, whatever boost pressure was in the intake was being fed right into the crank case. I contacted them and swapped it out for an oem pcv and all is well.