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Hi, my wife owns an Australian model 2005 LS focus with a 2ltr duratec engine.

It's recently begun using quite a bit of oil, like 2.5 litrs in 4000 kilometers.

I haven't noticed any smoke from the exhaust and the motor has only done 100 000 klm so I don't suspect rings or valve stem seals.

After searching a few forums, i came up with the idea that it might be the pcv vavle as the idle has also been rough.

initially I thought the pcv vavle was under the inlet manifold.

but after having a look there is pipe that comes from the cam cover that goes under the air box and connects into it on the inlet side of the air filter. It even has it's little own foam filter to stop any oil clogging up the air filter.

Anyway after checking ot out there look as as though there has been oil getting in the air box. I'm assuming the pcv valve is at the end that joins into the air box, I wasn't able to pull it off as it was hard to get to. Thinking about it now last time I changed the air filter is was covered in oil. I remeber thinking it was strange wut I didn't put two and two together.

I put a piece of electrical tape over the end of the connector on the came cover to see if this fixes the problem until I can get a new pcv valve.

My question is, is what i have described the actual pcv valve and pipe or am I looking at something different.

I couldn't see anything on the block, but it was damn hard to get a look in there.

All the posts i could find talked about the pcv being on the side of the block.

I will have a better look latter.

Has anyone had experience with this.

The other thing was that sometimes if I push the clutch in and let the revs drop the car sometimes nearly stalls but then revs up again by itself and it takes a couple of times of it doing this for the engine to settle.

This seemed to happen when the oil was low but then stopped when I filled it up.
 

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Look in the "duratec" section and search PCV or PCV delete.

The PCV is behind the intake manifold. Ive never looked behind the intake from under the car you might be able to get under it and check from below behind the intake to see if the hose is damaged.

If everything is working like it should, the air comes in from the top through the valve cover and then exits at the bottom behind the intake. Then the intake reburns that air. If the hose splits or developes a leak it then works backwards. Now its pulling in bad dirty air and blowing oil out the top into the throttle body.

So far what ive seen the 05 seems to have more issues with a split PCV hose. The 06 and 07 not so much that ive read.

Since the hose is behind the intake its not in a super bad place for really dirty air but if its split or cracked its still drawing in unfiltered air.

Its a little bit of work, if you can check and see if its split or cracked from the bottom first.
 

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I think actually removing the PCV valve on a Duratec involves removing the intake manifold unfortunately as the valve is under it. Unless there is a trick to getting it out that I don't know about (certainly possible).
 

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initially I thought the pcv vavle was under the inlet manifold.
It is under the intake manifold, and connected to the engine block. Older designs put the PCV valve on the cam cover, but it doesn't have to be there to do it's job of equalizing crank case pressures.

My question is, is what i have described the actual pcv valve and pipe or am I looking at something different.
You're looking at the oil breather that allows the crank case to breathe. If the crankcase doesn't breathe via the PCV and oil breather then rings wouldn't last very long. Engine power would be greatly reduced as well.

Anyway after checking ot out there look as as though there has been oil getting in the air box. I'm assuming the pcv valve is at the end that joins into the air box, I wasn't able to pull it off as it was hard to get to. Thinking about it now last time I changed the air filter is was covered in oil. I remeber thinking it was strange wut I didn't put two and two together.
Oil in the air cleaner is bad, most of the time that results from a condition called "blow-by" where oil is blown past the rings and back through the intake manifold. It usually collects in the air cleaner, and it does cause burnt oil out the exhaust but that is so little that it's usually not noticeable. When I've seen blow-by it's been on high mileage "little old lady" cars that weren't driven very often. It can happen on lower mileage vehicles, and other than overfilling oil by about a liter or pouring oil in the intake- that is the only way I know that oil will get into an air cleaner. Everything else you're experiencing fits with Blow-by- I'm sorry to say. I might be wrong, and you'll certainly be the owner of the youngest and almost lowest mileage vehicle I've seen with blow-by.

I put a piece of electrical tape over the end of the connector on the came cover to see if this fixes the problem until I can get a new pcv valve.
That's not going to fix anything, and I bet the tape has already fallen off. Even if you'd used duct tape it would've fallen off. If the PCV itself is clogged, then the crankcase pressures could be forcing oil through the oil breather to the air cleaner. It wouldn't go there as liquid oil, but rather hot oily mist. So now I'd expect to see oil all over the exhaust and windscreen when you drove the vehicle.

The other thing was that sometimes if I push the clutch in and let the revs drop the car sometimes nearly stalls but then revs up again by itself and it takes a couple of times of it doing this for the engine to settle.

This seemed to happen when the oil was low but then stopped when I filled it up.
That problem is related to the blow-by, and unfortunately fixing blow-by requires a new engine. In the chance that you have a stuck closed PCV and clogged oil breather (due to a lot of oil soaking the breather filter) then replacing the PCV valve, PCV hose, and oil breather filter would repair that problem. In this case when you check the PCV vacuum line with the engine idling you'll notice that the line will be collapsed. That's because engine vacuum is pulling, but the valve isn't opening.
 

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Discussion Starter #5
thank you whynotthinkwhynot for your very thorough reply I founf it really helpful.

I really hope it isn't blow by.

I got a new pcv valve and and managed to change it without removing the inlet manifold.

After doing some research I found it was possible to change to the pcv valve through gaps in the inlet manifold.

It wasn't easy but using some specialist tools it was possible.

I realised afterwards that putting tape over the cam case breather wouldn't help anything. The tape didn't come off by itself though, I had to remove it. 9it did have gaps at the sides to let some pressure through.

The breather foam filter in the air box was clogged up with oil and I will clean it as suggested.

There wasn't oil on the main filter as such, just a blackish residue just above the spot in the air box where the breather line enters the airbox and where the little piece of filter foam is located.

I disconnected the tube from the air box at the throttle body, when I opened the butterfly manually I could look down into the inlet manifold and it looked as though there was a residue on the wall of the inlet manifold. I suspected this was from where the pcv valve vacum line enters the inlet manifold. I cleaned the manifold with some throttle body cleaner.

There didn't look like there was any residue in the pipe going from the throttle body to the air box.

Now the pcv valve is changed I will check out the vacum line and see if it is colapsed at idle.

I will monitor the oil level and continue to post the results.

Do you think it is worth compression testing the motor?

What results should I expect to get for a wet and dry compression test?

If it turns out to be blow by do think it is worth complaining to Ford and trying to get out of warranty assistance, seeing as it is only low kilometers?

Thanks for the advice guys.

Cheers Dan
 

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I did the PCV delete because i was having idle issues but mine wasnt cracked. I still did the delete even though it wasnt an issue just so ide know it would never be a problem again.

I was then told i needed to replace the line from the intake to the top of the cam cover but i couldnt quite wrap my head around why to do this.

Then the next oil change after i did the PCV delete my oil looked REALLY bad. And i also noticed oil in my intake near that tube it was actually sucking oil from the PCV and up and out the cam cover.

Now i get it. Lucky i didnt run it long that way. I could of relally done alot of damage if i had continued to run it that way.

Im planning to swap out my throttle body so ill see how it looks then if its still clean. I plugged the intake tube on the intake and put a filter on the cam cover. I believe its working right now.
 

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Well insted of pulling air in from the top and blowing it out the bottom back into the intake manifold i plugged the manifold so i know its no longer leaking due to a bad hose, cracked, split, collapsed what ever. Then i cut all the guts out of the PCV fitting so its just a right angle vent.

So now it just vents out into the air like the older cars do. Rather then reburning it.

I also added a line so it dumps out over near the starter kinda. If any oil drips out it dumps it out down over behind the starter.

 

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Discussion Starter #10
A quick update.

I changed the pcv valve (without removing the inlet manifold) a about four weeks ago and intially all looked ok, with no noticeable oil usage.

On a long trip away for the weekend we covered about 800kms.

After we got back the oil level looked ok.

I checked the oil again today and I put about a litre in. (Unfortunately I didn't take note of the mileage when I changed the pcv.)

I also did a wet compression test today and intially all the cylinders got about 230psi except for number two cylinder which came up with about 110psi. The spark plug on number two was also quite fouled with a light brown caked on substance and looked to have oil residue on the back of the L shaped part of the electrode.

However on the second run through it came up to 230psi like the rest, it took a few more cranks to get there though than the other cylinders.

On the third run the first two cylinders were getting about 250psi (I didn't bother doing cyclidners three and four again.)

I'm guessing the compression increased as more fuel filled the pistons and became wetter sealing the pistons more precisely?

My brother who is a mechanic with Toyota suggested that the piston rings in number two cylinder may have become stuck at some stage causing the rings to wear unevenly and then after an oil change and flush the rings could become free again and moved slightly not seating correctly to the bore? An that 'maybe' it might reseat again with driving.

Anyway I beleive it is using less oil than before with the new pcv valve, I will have to monitor it precisely to see.

Any comments or suggestions very much appreaciated.

My brother suggested to precisely monitor the oil level for changes.
 

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I think actually removing the PCV valve on a Duratec involves removing the intake manifold unfortunately as the valve is under it. Unless there is a trick to getting it out that I don't know about (certainly possible).
you can change the valve using extra long 90o and straight needle nose pliers, just finished doing this last week without removing the intake manifold
 
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