PCV= bad idle

[Dvious]

I did a search but i really could not find anything, i replaced the pcv valve today the old one was covered in grease and gunk , anyway i blew into it one side blows thru the other let some air past but not much. after i replaced it car idled high after it warmed up the idle dropped back to normal 750-950rpms, but the idle was surging all over the place????? also when i turne the air conditioning on the idle shot up to 3000 grand and didnt adjust back down????? whats up with this anyone else have this problem??? i dont think its my ISC because before i replaced the pcv it would kick the idle back down when i turned the air on.

 

[olmytsi]

Make sure you don't have any leaks at the pcv and the hose that goes to it.

 

[kenamond]

Did you replace the PCV with an OEM part? If not, it might not be properly limiting the air at idle. It's a fact that the PCV valves at Autozone, Carquest, etc. do not work on our cars. The problem with these, however, is that they don't seal up under boost, but it might also be that they don't properly limit air at idle. The PCV does more than just close under boost; it also variably limits air flow out of the VC (based on IM vaccuum level).

Anyway, if that's all you changed, you might have a bad PCV or as olmytsi said, you have a leak in your PCV->IM line or connections.

 

[blackbyrd]

Did you replace the PCV with an OEM part? If not, it might not be properly limiting the air at idle. It's a fact that the PCV valves at Autozone, Carquest, etc. do not work on our cars. The problem with these, however, is that they don't seal up under boost, but it might also be that they don't properly limit air at idle. The PCV does more than just close under boost; it also variably limits air flow out of the VC (based on IM vaccuum level)

Actually most PCV valves don't hold upto boost. I've tried 3 OEMs and a couple aftermarkets, and none one of them will hold 20psi.

http://dsmtuners.com/forums/showthread.php?t=229338

 

[Dvious]

Miracle my car is running perfect again and i did not touch anything, a little weird but hey it works. thanks for your guys help. what i did notice is that my valve cover now has hairline crack in the right above the valve

 

[hereitcomes]

your going to leak oil when boosting then. Make sure you get that fixed.

 

[Blue95GST]

and how you said in the beginning air blew through one side fully, and a little the other way, air should only be able to flow one way through the PCV valve, if it can in any way flow both ways, its bad and needs to be replaced, good luck with everything

 

[Dvious]

Finally hit 16psi today and my idle is back to normal, seems like turbo spolls much faster know, would a pcv valve have an effect like this? always felt like my car was choking and only would hit max boost of 10psi??? is this normal from a pcv valve change??

 

[Blue95GST]

yes a clogged pcv valve will hold alot of your car back, congrats on the fix and stay boostin

 

[Dvious]

This sucks My idle surge is back, i know this is weird but it poured all day yesterday here driving to work in the morning was fine but after work driving through puddles and the pouring rain i pulled in my driveway to cool down and the damm idle surge is back!!! Kinda weird huh???