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Topic: PCV on 5.0 (Read 4455 times) previous topic - next topic

PCV on 5.0

I believe some problems I'm having are linked to the pcv valve - be it the valve being plugged, grommets being bad, or the hose plugged. I've been having to refill the oil frequently and idle was rough although seems to be better now (I take it that the cooler weather is helping). The issue is that my Haynes manual shows a location for it on a carbed 302, not the fuel injected. Anyone have a description on where to find the thing?
1988 Thunderbird Sport

Re: PCV on 5.0

Reply #1
Well after looking online for HOURS, I found a couple people claiming that its on the back center of the lower intake...so is there an easy way to get to this? I have like 2" of space back there and most of that space already has wires and things running from place to place. I don't think I can fit my hands back there without taking the upper manifold off.
1988 Thunderbird Sport

Re: PCV on 5.0

Reply #2
The pvc valve is on the back of the lower intake it has a big hose connected to it its a pain to get to. Also I've heard that the metal pvc valves suck and they cause problems like the engine eating oil you should get the plastic pvc valve.
[SIGPIC][/SIGPIC]
87 T-Bird turbo'd and supercharged and if things call for it juiced. :evilgrin:
88 Turbocoupe t3, 4.10's, Daily driver

Re: PCV on 5.0

Reply #3
This might help.

Re: PCV on 5.0

Reply #4
Seek tell me how this comes out because i am having the same problems and have no clue whats going on, my engine will revv real high on start and sometimes when im driving. Its happened to me at a few lights i press the brake (totally letting off the gas) and it'll start to revv high and wanna go.And i have the same problem with oil, having to refill it ever so often.

Re: PCV on 5.0

Reply #5
I'll try jamming my hand back there today if possible (upper intake's in the way) and feel around. Mirrors may help with finding it. If I manage to get it unplugged (just pull out), I'll take pictures of the easiest way to get to the thing. Otherwise it may have to wait until I have the time and weather permits to drain the coolant to take the intake off.

If the valve still rattles when you shake it, there's a good chance that its okay and the problem lies elsewhere (pcv hose possibly). You may also want to try http://www.fordmuscle.com/archives/2002/01/tenpin/index.shtml to see if that helps your idle.
1988 Thunderbird Sport

Re: PCV on 5.0

Reply #6
Quote from: 20th anny 5.o
Seek tell me how this comes out because i am having the same problems and have no clue whats going on, my engine will revv real high on start and sometimes when im driving. Its happened to me at a few lights i press the brake (totally letting off the gas) and it'll start to revv high and wanna go.And i have the same problem with oil, having to refill it ever so often.


What does it Idle at?  Does it idle high or is this just like an intermitent problem?  If its high all the time,  it could be a vacuum leak,  TPS too high,  IAC sticking.    If its intermitent it could be a lean surge caused by dirty injectors,  or a dirty throttle bore.

Re: PCV on 5.0

Reply #7
Easiest way I can describe finding the PCV valve is this:

On the underside of the upper intake, driver's side, is a metal fitting to which vacuum lines are attached. Find the thickest one, and follow it to the back of the engine. At the end of that hose is the PCV valve. Pull up and the valve is out---simple as that. That hose can only go so far, so installation shouldn't be terribly difficult. What sucks is that you simply cannot see the PCV valve location...it really has to be done by feel. But once you've done it you won't forget. It may also help to remove the MAP sensor bracket and let it hang, giving more room behind the engine for your arm.

Re: PCV on 5.0

Reply #8
I got it out, but I have no idea how its supposed to sound when "clogged". There were a few chunks in it but those washed right out. I don't see why they'd need to be replaced if 20 seconds under water seems to clean them up. It rattles, but thats the shaft in the inside moving. Up/down and it seems as if water can clean that out. Any ideas on what to look for if need of replacement? It may not be clogged but I guess it could still be a bad valve.

and is it supposed to be covered in oil when taken out? I thought only gases were supposed to be near (or going through...unsure if oil was on both ends) the thing.
1988 Thunderbird Sport

Re: PCV on 5.0

Reply #9
it was hard to get pictures back there but I have the general location pictured and one from behind the intake.




Just grab onto the hose at the bend and pull up, the valve will most likely come out with the hose (did with mine...but mine has its own issues. I don't think there was a grommet on it). Like Eric said, installation isn't too hard. I just felt around for the hole with my finger and once I found it, plugged the valve back in.

So it looks like I found the cause of losing oil - the pcv hose was dripping with it when I took the valve off. I take it a functional valve and new hose are in order, yes?
1988 Thunderbird Sport

Re: PCV on 5.0

Reply #10
The PCV valve doesn't seem too hard, but i've heard that a clogged up condensor filter underneath the PCV can also cause oil leak problems. Anyone have an easy way to replace the filter as well? I'm having a tough time of it cause it's all the way down there, and it seems like a good thing to do while the PCV is getting replaced as well.
1984 Cougar Convertible
1988 Cougar XR-7

Re: PCV on 5.0

Reply #11
Quote from: 4thqtr
The PCV valve doesn't seem too hard, but i've heard that a clogged up condensor filter underneath the PCV can also cause oil leak problems. Anyone have an easy way to replace the filter as well? I'm having a tough time of it cause it's all the way down there, and it seems like a good thing to do while the PCV is getting replaced as well.


Take a long sheet metal screw and thread at least a inch into it, then you should be able to pull it out with a pair of plires. If you like rather than replace it, you can dissamble it and the wire screen cleaned with carb cleaner.

Re: PCV on 5.0

Reply #12
Is there anyway that someone could point out a MAP sensor, while there are pictures up?
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Re: PCV on 5.0

Reply #13
for 10 or i5 bucks I would replace the screen, pcv, and gromet  all parts should be avilable through partsamerica.com aka advance auto

Re: PCV on 5.0

Reply #14
Quote from: 20th anny 5.o
Seek tell me how this comes out because i am having the same problems and have no clue whats going on, my engine will revv real high on start and sometimes when im driving. Its happened to me at a few lights i press the brake (totally letting off the gas) and it'll start to revv high and wanna go.And i have the same problem with oil, having to refill it ever so often.


Could this be a brake booster problem?