pcv?

monster · Jun 17, 2013

i have a 97 cobra and they is oil going into intake through pcv

i have put 3 or 4 pcvs on and all do the same

as soon as you start car up you can hear it opening and closeing really fast .... acts like its go to much crank case pressure what can cause this ?

also put a catch can inline with pcv and it still clicks like its opening and closeing

mikey94gt · Jun 17, 2013

Hmmm..... how many miles on this beast? and do you use oil? does it smoke out the tailpipe on startup? Also, what kind of mods do you have? The catch can is a good idea, does it fill up quickly? tell me a story!!! SOunds like you might have a bit of a blow-by problem. I hope not, lol. All engines that use a Positive Crankcase Vent will get oil in the intake, but excessive puddling is a problem. The catch can is a good idea, does it fill up quickly?

monster · Jun 17, 2013

107k on body it spun a rod bearing last may and was rebuilt stock pistions i dont know the full story it was done before i bought the car all i have is recepit .... any ways about 10k on motor since that ... car is pretty much stock it has o/r x pipe slplm2 , hurst shifter, 4:10 gears few supin mods springs cc plats ect.... car runs goods and pulls hard ive had 3 cobras this one is stout to be pretty much stock... it all depends on how you drive it if you baby it it want use no oil or smoke on start up if you drive it hard it will sometimes smoke on start up and it uses about a shot of oil a month if i drive it hard on weekends.... you can hear the pcv clicking(opening & closeing) really fast while its idleing... vacume on intake seems to be strong ... i havent done a compression test yet i will this weekend tho.... im lost just hope it ant rings lol... thanks man i need some insite is they a way to check the vacume on intake to make sure its right or could they be a clog some where?

monster · Jun 17, 2013

also have mil's on rear o2's and it through a bank 2 too lean code last week cleared it and now its bank 1 and 2 are lean ... ive changed fule filter and put a new air filter on it cleared codes again drove 100 miles befor it came back on.. could this have somethig to do with it or what could cause it to run lean thanks

MustangChris · Jun 17, 2013

I'd suggest putting a catch can on. that way you can gauge how much oil is transfering.

Oil is a strange thing... if you drop a single drop on a floor and let it sit for an hour, that drop will look like the size of a watermelon (exaggeration, but you get the point. lol)

THe same thing happens in your intake. jsut a few tiny drops get pulled in every once in a while, then you let the car sit over night, pull the intake and youre like "omg! There's a half-quart in here!" -- the catch can will help put a quantity on whats getting transferred.

Next I suggest pulling your plugs and seeing if you are indeed running lean or burning something.

mikey94gt · Jun 17, 2013

Chris... hes got a catch can... read the OP's first post... lol

Hm.... I really wanna see what the compression check says. IM hoping for about 1-4% spread, and hoping you can do a leakdown check as well, that will tell the whole story.

Your vacuum can be checked from any port... just hook up the vacuum gage, and see what ya got. it should be between 12-20" of mercury at idle, and swing wildly when the throttle is blipped.

I wonder who did the rebuild, and if they put new rings in the bores while they are glazed. if you run it hard, and it smokes a bit, then im skeptical of their rebuild.

The easiest way to see if the intake is clogged, if you're running lean, etc is to read the plugs.

burning oil can trick the o2 sensors into thinking its running lean.... and your using just enough oil to do that I think.

Oh, and while you're checking things out, pull the codes and post them... along with the fuel pressure. this will give us a good idea of what you're working with, and its easy to do.

monster · Jun 18, 2013

thanks ill post #'s of compression test when i do it.... i still drive the car everyday will this hurt it ? car runs good and all thanks again

vermilion · Jun 18, 2013

Pcv always opens and closes. Pcv acts like a speed bleeder for brakes. Air keeps it open. Hydraulically it closes as oil pushes the valve. Best bet is deep welled pcv catch can.

Sent by smoke signals

monster · Jun 18, 2013

should it do this at idle tho? thanks

MustangChris · Jun 18, 2013

good eye on the catch can, mikey. I thought he was asking if he got one would it effect the PCV from opening/closing.

So, to answer another one of your questions, yes, the PCV will be operating while at idle.

its, as far as i know, impossible to "clog" your intake. Obviously debris can get in there as well as build up. This build up can limit your flow, as well as cause excess turbulence inside the intake tract.

If a vacuum line is clogged, you're in for a huge hunting game... -- but i wouldnt worry about either of these things. As mikey said, your first step is to diagnose the compression and to trouble shoot blow-by.

mikey94gt · Jun 18, 2013

I forgot to address the pcv valve lol. And I'll keep an eye on this thread to see what's up...

as far as the pcv goes, I've never heard one click around before, but I know they open and close at idle and such, as the crankcase pressure fluctuates, and it will do that more as the engine gets worn and cylinder pressure works its way past the rings. I hope to figure out a good diag for ya, but we need info first!!!

I wouldn't worry about driving it, it's not gonna hurt it unless you run outta oil.