PCV question..
PCV question.. simple question about pcv..i tried searching but i found many different answers..can a broken\leaking pcv hose cause misfiring? my 90 degree PCV hose broke, i quick fixed it for now but car is kind of misfiring or shaking at idle only..could pcv do that? to my understanding it sucks up more air to the cylinders so injectors compensate by more fuel, almost like a vacuum leak. is that correct?
its not like almost a vacuum leak. it IS a vacuum leak. since you fixed it, have you "reset" the pcm with a tool or leaving the battery unplugged? that will clear any dtcs and reset the fuel trims. if the misfire comes back, it wasnt the pcv hose you fixed. luk.
am pretty much confused.. the 90 degree hose will not suck air..i pluged it completely just to test if its causing the bad idle and nothing changed..i think i will re do the whole install for the peace of mind..
again with this? My **** was broken eaten thru for years and it did not affect my car at all! I fixed it because I was in there doing some work. My gas mileage did not change either was. I believe you have other issues.
disconnect the battery tonight and reconnect it tomorrow morning, see what happens, and then luk.
i blocked all the leaks, fixed pcv permanently and car still idles weird, am not saying bad but it shakes randomly sometimes 
its a vacuum leak for sure then right? going to order new gaskets and re do the install..
its a vacuum leak for sure then right? going to order new gaskets and re do the install.. Trending Topics
TECH Apprentice
Joined: Sep 2011
Posts: 344
Likes: 1
From: La Porte, TX
Turn key on, don't start car
Pull PCM BATT and PCM IGN fuses in engine compartment
Wait 5-10 min
Turn ignition off
Replace fuses
Start car.
BTW, idle will be grumpy after resetting it this way for a few minutes until it relearns.
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Verdad Gallardo b4 spending that money, get a can of brake clean or carb cleaner, and spritz it everywhere that is after the MAF and before the intake port of the cylinder head. any air getting in between those two points could cause some problems. i dont remember what year your car is, but that includes EGR, PCV, leaks around the IAC, manifold gaskets, rubber tube between the MAF and T/B, MAP sensor in back, brake booster, fuel injector o-rings, etc. all that good stuff. a leak letting in air between the MAF and cylinder head intake port constitutes a vacuum leak. luk.
b4 spending that money, get a can of brake clean or carb cleaner, and spritz it everywhere that is after the MAF and before the intake port of the cylinder head. any air getting in between those two points could cause some problems. i dont remember what year your car is, but that includes EGR, PCV, leaks around the IAC, manifold gaskets, rubber tube between the MAF and T/B, MAP sensor in back, brake booster, fuel injector o-rings, etc. all that good stuff. a leak letting in air between the MAF and cylinder head intake port constitutes a vacuum leak. luk.
Have you checked the spark plugs to see if one of the banks is running rich, if one is then check for a exhaust leak on that side of the engine.
oh and one more thing! if i want a better seal on the map sensor what should i do? silicone? ideas? am going thru the install in my mind and see if i missed something lol...
i can clearly see how i might be having a vacuum leak!! going to install it after tomorrow. any input on sealing the map? put a little silicone on the "barbs" of the rubber seal on the map. just a dab. it (the rubber seal) will likely be ruined if you have to take the map out later, so be sure to source another one for your toolbox.
i reinstalled the intake yesterday. used new gaskets, torqued the bolts in sequence, connected everything just perfect. started the car up and it idled great, drove it to my friends house and as soon as i parked it there the bad idle came back again it idled VERY bad for a while then it got better but still bad. hooked up a scanner and it reads no codes?! only egr and air!!! now what? please help am sick of this do i need a tune after egr delete?