What the...?

BurningRubber

10 Year Member
Dec 6, 2004
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Ok, so my Mustang uses a little oil, which kind of makes me mad cause its only at 100k, but Ive NEVER seen smoke come out of the exhaust, even when watching videos of me racing.

So, that kind of had me stumped.

However, I noticed that when I took my plenum off a while ago to clean it, there was quite a bit of blowby looking stuff and a little oil in there.

The other day, I was changing the boots and springs on my COP's and noticed that some of the boots had oil on top of them.

So I guess the consumption is coming from a leak. But my question is, why is it getting sucked back into the plenum and intake, and how in the hell is it getting near/around/in my plug wells?!?!

Is this a PCV issue, or something else? All I can think of is the PCV is clogged and causing soem excess pressure or blowby to occure and making oil go in weird places. Possibly if the PCV is clogged the pressure buildup is forcing small amounts of oil to seep out around the top of the valve covers and onto the intake manifold around the plugs?

Next question is, is there one, or two PCV valves... or is one a beather, and the other the PCV? And which side is what on? If I had to guess id say the PCV is on the passengers side (on a 2000 engine) and the breather on the drivers side... cause the one on the passengers side has Motorcraft stamped on it, dont think the other one does.

So any help is appreciated, I just thought it was kind of weird. If its possible to get this thing to stop using oil that would be sweet. I hate checking it with our dumbass dipsticks, and dont like worrying about it running low.
 
BurningRubber said:
Ok, so my Mustang uses a little oil, which kind of makes me mad cause its only at 100k, but Ive NEVER seen smoke come out of the exhaust, even when watching videos of me racing.

So, that kind of had me stumped.

However, I noticed that when I took my plenum off a while ago to clean it, there was quite a bit of blowby looking stuff and a little oil in there.

The other day, I was changing the boots and springs on my COP's and noticed that some of the boots had oil on top of them.

So I guess the consumption is coming from a leak. But my question is, why is it getting sucked back into the plenum and intake, and how in the hell is it getting near/around/in my plug wells?!?!

Is this a PCV issue, or something else? All I can think of is the PCV is clogged and causing soem excess pressure or blowby to occure and making oil go in weird places. Possibly if the PCV is clogged the pressure buildup is forcing small amounts of oil to seep out around the top of the valve covers and onto the intake manifold around the plugs?

Next question is, is there one, or two PCV valves... or is one a beather, and the other the PCV? And which side is what on? If I had to guess id say the PCV is on the passengers side (on a 2000 engine) and the breather on the drivers side... cause the one on the passengers side has Motorcraft stamped on it, dont think the other one does.

So any help is appreciated, I just thought it was kind of weird. If its possible to get this thing to stop using oil that would be sweet. I hate checking it with our dumbass dipsticks, and dont like worrying about it running low.


You can also do a quick compression test. That would rule out bad piston rings or valve guides. You should also get an aftermarket oil pressure gauge. The stocker is a huge POS.

How much oil is it burning? I think like 1 quart every 3000 miles would be acceptable. I mean c'mon, we drive fords:rlaugh:
 
the98stang said:
You can also do a quick compression test. That would rule out bad piston rings or valve guides. You should also get an aftermarket oil pressure gauge. The stocker is a huge POS.

How much oil is it burning? I think like 1 quart every 3000 miles would be acceptable. I mean c'mon, we drive fords:rlaugh:
my stang's never burnt oil:shrug: yet my bros T-Supra is almost a two-stroke:rlaugh: still pawns:nonono:
 
the98stang said:
You can also do a quick compression test. That would rule out bad piston rings or valve guides. You should also get an aftermarket oil pressure gauge. The stocker is a huge POS.

How much oil is it burning? I think like 1 quart every 3000 miles would be acceptable. I mean c'mon, we drive fords:rlaugh:


Well, im fairly confident that it isnt burning oil, but a compression test is a good idea... I will try to do one when I change the plugs next (coppers, so it wont be too long), this is one motor im actually afraid to do a plug change on...:nonono: so the less I have to pull them, the better I feel.

It seems like its right around, maybe a little less than a quart per oil change, which is 3k for me. Its just weird cause I have a Jeep with an inline 6 that has almost 160k on it, the last 30k werent easy miles either, and it doesnt use any between changes.
 
Passenger side valve cover has the PCV valve in it.

Some oil consumption is normal, according to Ford. My air/oil separator is full after driving one full gas tank, and that's with 8k miles on the car.

How much oil are you losing? What viscosity oil are you using?
 
sgarlic said:
Passenger side valve cover has the PCV valve in it.

Some oil consumption is normal, according to Ford. My air/oil separator is full after driving one full gas tank, and that's with 8k miles on the car.

How much oil are you losing? What viscosity oil are you using?


Cool, thats which one I thought it was.

It seems like its around a quart, or just under every 3k. But like I said, it doesnt seem like its an internal thing, I think its blowby and leaking a little from some kind of excessive pressure from the way its built up on and around the plug wells. Its 5w30 Motorcraft btw.



the98stang: I dont use anti-seize on them and I tighten untill snug, and then 1/8th or a 1/4 turn past. Still makes me a little anxious with all the horror stories though...
 
BurningRubber said:
Cool, thats which one I thought it was.

It seems like its around a quart, or just under every 3k. But like I said, it doesnt seem like its an internal thing, I think its blowby and leaking a little from some kind of excessive pressure from the way its built up on and around the plug wells. Its 5w30 Motorcraft btw.



the98stang: I dont use anti-seize on them and I tighten untill snug, and then 1/8th or a 1/4 turn past. Still makes me a little anxious with all the horror stories though...


don't use the "1/4 turn" rule. You NEED to use a torque wrench. Torque is the key to those things
 
the98stang said:
don't use the "1/4 turn" rule. You NEED to use a torque wrench. Torque is the key to those things
Agreed, we went out and bought an inch/lb torque wrench for my cam swap but the thing has been priceless when it came to all the times we had to pull the plugs, check them, and retorque them down during the install. The way I see it, a $65 wrench is good insurance against a plug blowout that could cost a grand...
 
Ok, changed the PCV valve with a Purolator one, we'll see if that changes anything.

The vaccum line that ran from the old PCV into the plenum had some oil in it. The old PCV seemed like it was stuck open, it still rattled around but it didnt close off like the new one did. Possibly if it was stuck open oil was getting sucked through that vaccum line into the plenum and getting burned off in small amounts.

So the one on the drivers side valve cover is just a vent? Thats what it looks like to me... its just plugged into the valve cover pretty securly, not like the PCV.
 
Rickyll7 said:
why not use anti seize?


Its a lubricant to a certain extent, if it keeps things from seizing up. It will allow the plugs to back themselves out easier.

I beleive anti-seize is only reccomended for long life plugs that wont be changed for 50k+ miles, basically something thats going to be in there for a long time. Running coppers that need changed every 10-15k I dont think theres a need for it. I didnt use any.
 
BurningRubber said:
Cool, thats which one I thought it was.

It seems like its around a quart, or just under every 3k. But like I said, it doesnt seem like its an internal thing, I think its blowby and leaking a little from some kind of excessive pressure from the way its built up on and around the plug wells. Its 5w30 Motorcraft btw.



the98stang: I dont use anti-seize on them and I tighten untill snug, and then 1/8th or a 1/4 turn past. Still makes me a little anxious with all the horror stories though...


ALARM! ALARM! ALARM! DO NOT SIMPLY SNUG YOUR PLUGS AND THEN TURN THEM 1/4 TURN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1

Use TORQUE WRENCH and torque to 13 ft. lbs. Using a VERY thin coat of COPPER BASED anti-sieze on the THREADS ONLY is also a good idea. DO NOT get any on the end of the plug though. I've changed a gaZillion of them this way with great success.