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Discussion Starter · #1 ·
can some one explain what has to happens when you pull out the pcv valve..?

When my car is running and i pull out that pcv valve complete nothing happens not even a shake in the rpm..?

also im burning a little oil suddenly and all 6 six of my sparkplugs are black as the night.

do i have leaking valve seals..? or what else, need help, sick of the smoking now...:(
 

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Hi Robii ,

If the valve seals/guides are worn you will get a puff of blue smoke on start up then it will dissapear , also if they are worn when you stomp on the gas you would get a puff of blue smoke then it goes away . Worn piston rings/bore = blue smoke all the time.

As for the PCV valve i can't help much on that , sorry man
 

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That should indicate that you already have an inlet leak somewhere.

Or is the PCV valve blocked? Then pulling it out wouldn't make much difference.
 

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If you pull out the PCV from the valve cover, and nothing happens, that means your PCV isnt doing anything. Its normal function is to pull vacuum from the valvecovers and into the intake. The stock PCV doesnt hold up well to boost, so its probaly shot.
oil burning can be many of things, valve seals wouldnt be my first guess.
 

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valve seals = blue smoke during cold start or after sitting for a few hours...could also be your valve guides too.

high rpm = piston rings. do a compression test and see what your numbers are...then drop a tablespoon of oil down each one and try again...if numbers increase...then you know you're problem.

pcv= intake leak and/or shot pcv valve...your car should stall when you remove it from the valve cover.

running a catch can or inline filter on the pcv hose will help with some oil consumption due to blow by. inline filter should have the inlet/outlet running on top, while having the resevoir at the bottom to contain the oil.

JACK.
 

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Discussion Starter · #6 · (Edited)
okay, i dont have smoke at startup, the smoke comes when the car is warm, so after a 5minutes of driving. Then the smoke comes when i accelerate and and a few minutes later also when idling. Not with high rpm then its gone...

when i blow and suck on the pcv valve it is okay.. its like theres no pressure or vac that it not stalls.

and why are all sparkplugs black do you think??

thank all
 

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black is from unburnt fuel. your pcv valve should rattle if you shake it, you shouldn't have to add pressure to check it.

have you done a compression check yet? that'll tell you lots....

JACK.
 

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Discussion Starter · #9 ·
okay did a compression test and tryed some other things...

compression test is not a beauty but dont know if thats the problem.

front row from left to right
128psi 130psi 130psi

rear rear from left to right
150psi 150psi 150psi

looks a little weird but also found out i have a very weak spark.
first spark is bright then the rest is not even half that bright.

spark plugs still black also top of new pistons look dirty/black... Fuel problem ?
 

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do u have a spare disty? u might wanna try swapping a disty and see if the spark improves, cuz' it looks to be the first signs of the ignitor failing.
the weak spark could cause incomplete combustion and fouled up the plugs.

edit: just checked your car domain and u have HEI. so nvm. maybe check your wiring?
 

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I had talked to you about this maybe a month ago now but I think you have a vacuum leak on the manifold somehwere. Did you ever pressure smoke it to look for leaks?

I had to pressure smoke mine to find out the thermal spacer gaskets were leaking. It was not audible, and not visible, but there was a leak. I had the same problem as you, could pull off any vacuum line and not have any change in RPM. When you pull off any vacuum line on the IM your RPMs should jump above 2000. (considering your idling about 750-1000)

To me its not to strange that this happens just after you do a motor swap.

Blowing on the PCV doesnt tell you anything because you can make about 1 Psi with your lungs and mouth unless you are superhuman. I have had 3-4 leaky check valves that seemed kosher when you blow on them.
 

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Since the numbers on the front bank of cylinders are so far off from the rear numbers, could your timing belt be off by one tooth for the front cam?
 

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that wont be the oil problem no. but it might be the compression problem...if its not try a tablespoon of oil down the rear bank and check your numbers again.

its an easy way to check your rings out. i'd recommend doing that to all 6 before tearing anything off.

JACK.
 

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If you pull out the PCV from the valve cover, and nothing happens, that means your PCV isnt doing anything. Its normal function is to pull vacuum from the valvecovers and into the intake. The stock PCV doesnt hold up well to boost, so its probaly shot.
oil burning can be many of things, valve seals wouldnt be my first guess.

Normally our cars will stall out if you pull the PCV because of the design of the system that directly connects engine vacuum to the crank case. Hence why the cars stall when you leave the oil cap off. If you are running megasquirt MAP sensor your car wont stall because the map can account for the air leak where the OEM VAF system cant.

When you boost our KL motors you really need to un hook the PCV lines from the intake manifold & re plumb them through a catch can then back to the pipe the air filter is on at the turbo inlet. If you do not do this you can and will boost your crank case via the turbo... not exactly what you want. Yes the PCV valve has a valve in it, but the other PCV hoses have full open valve cover to intake manifold.

Look at a factory boosted car like the supra... it's PCV all gets sent back to the turbo inlet & not to the intake plenum(manifold)

As for your compression issue if you have KLDE or KLZE compression ratio pistons in there those numbers are terrible results. Do you have a past compression test of the car to compare?
 

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Since the numbers on the front bank of cylinders are so far off from the rear numbers, could your timing belt be off by one tooth for the front cam?
Timeing shouldnt have anything to do with it, unless your valves werent moving at all. As long as the valves open and close, you should be able to do a accurate compression test even it was so out of time it wouldnt run.

When you boost our KL motors you really need to un hook the PCV lines from the intake manifold & re plumb them through a catch can then back to the pipe the air filter is on at the turbo inlet. If you do not do this you can and will boost your crank case via the turbo... not exactly what you want. Yes the PCV valve has a valve in it, but the other PCV hoses have full open valve cover to intake manifold.
I got like 5 KL motors, 2 that are sitting on a floor in my garage for full exploration.. Ive gone through them so many times its rediculous. There is a hose on the rear vc and the front VC that are T'd together under the thottle body and behind the IM, This T goes directy to a large hose that is plumbed into the 90deg plastic elbow on the intake before the throttle body.
The 3rd hose going to a VC is on the front top of the VC, it has a PCV valve mounted on it and goes directly to the Intake manifold.
The design is that the PVC would allow vacuum pressure to be drawn into the crank case, it would suck fumes out via the 2 T'd hoses, and it would draw in fresh air from that intake elbow. Occasionally you get blow by, wich is oil being pushed into that intake elbow (opposite direction of how it should be functioning) This is where you would put a catch can, before that elbow.

On a turbo setup, that line would go before the turbo inlet.

Simply put, the stock PCV on our cars is not design to restrict positive air pressure. You wont find them on any factory Turbo cars. You need a PCV from a factory turbo car if you wish to keep the correct function of the PCV system

Unhooking your PCV system and plugging all the lines will trap fumes inside your motor and destroy the life of your oil and motor quicker. Venting your PCV system (just unhooking and leaving the hoses open) Will cause similar, however you will get more blow by, and less effeciency of how the system was intended to work.

Hope all that makes sense, if not. Simple diagrams

Stock


Turbo
 
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