Burning Oil?

[Gussie2000]

I am sorry but you did not say that re read your post! I have had issues with the pcv valve, and that is that. I still lose 1 qt every 3000 miles , and would consider that normal. When the pcv valve sticks and I lose 2 qts in 1000 miles that is not normal. And doing what I have done to get rid of the pcv valve has brought it back to 1 qt every 3000 miles and that is fact , not what someone told me. So I do not care if your mechanic says I am wrong I know that my problem is fixed . And be sure to print out your post and ask him if that is what he said. shawn

Ok,let's not get passionate about this one my fellow VXer,i quite sure this issue has been on the table many times.

However i use the word lifters to explain my self somehow & the mechanic just brief me about the oil compsumtion & the experience he had in the past & what can be the possible reasons the engine's burning oil.

My warranty covered all the cost,i just went & drove off out the shop.

Yes,it's normal to have some sort of oil loss between oil changes,we all agree in this one.

I believe that if the PCV wasn't necessary for all modern engines then why is there for ? probally i'll follow you on the PCV issue & get rid off it so i may be able to loss less oil as you do.But my VX doesn't burn as much as 1 Qt every 2000 miles

The noise i had in my engine was the tipical ticking noise,right at the top of the engine,my mech solve the problem & the engine runs as quiet as you can imagine the work is covered with 50.000 miles or 5 years.

I regret not to step by at the shop & had a look at the open engine so i can gain more knowledge about how the isuzu 3.5L engine works.

Plus your input was refered in your personal experience agains my mechanic.Your believe the problem was solve by getting rid of the PCV,my problem can be the rings or otherwise,who knows.

What the mech meant afterall is that isuzu fail to support its customers by ignoring the issue,they turn their back on you,me & all the rest of us whom purchased their products.

I not sure,but i think the engine you are talking about is the 2004 3.5L with the direct injection system that came with the axioms which really needs the ECU software upgrade & the wiring harness replaced if you want it in the VX

If i had the opportunity i'll deffinetly drop a 2004 engine into the VX.

[Ldub]

Ok,let's not get passionate about this one my fellow VXer,i quite sure this issue has been on the table many times.

However i use the word lifters to explain my self somehow & the mechanic just brief me about the oil compsumtion & the experience he had in the past & what can be the possible reasons the engine's burning oil.

My warranty covered all the cost,i just went & drove off out the shop.

Yes,it's normal to have some sort of oil loss between oil changes,we all agree in this one.

I believe that if the PCV wasn't necessary for all modern engines then why is there for ? probally i'll follow you on the PCV issue & get rid off it so i may be able to loss less oil as you do.But my VX doesn't burn as much as 1 Qt every 2000 miles

The noise i had in my engine was the tipical ticking noise,right at the top of the engine,my mech solve the problem & the engine runs as quiet as you can imagine the work is covered with 50.000 miles or 5 years.

I regret not to step by at the shop & had a look at the open engine so i can gain more knowledge about how the isuzu 3.5L engine works.

Plus your input was refered in your personal experience agains my mechanic.Your believe the problem was solve by getting rid of the PCV,my problem can be the rings or otherwise,who knows.

What the mech meant afterall is that isuzu fail to support its customers by ignoring the issue,they turn their back on you,me & all the rest of us whom purchased their products.

I not sure,but i think the engine you are talking about is the 2004 3.5L with the direct injection system that came with the axioms which really needs the ECU software upgrade & the wiring harness replaced if you want it in the VX

If i had the opportunity i'll deffinetly drop a 2004 engine into the VX.

The PCV (Positive Crankcase Ventilation) valve, came about sometime in the sixties IIRC, it was a measure taken in an effort to reduce air pollution.
Before that, excess crankcase pressure was vented into the atmosphere through "breathers", either on the valve covers, or sometimes through the oil fill cap...

This has been a presentation of "Your internal combustion engine & you, the early years"...

[psychos2]

It is not so much the fault of the pcv valve as it is the fact that there is no baffle to stop the oil from being sucked from the valve cover. In other engines the failure of the pcv valve does not have the same affect as it does in the 3.5 . shawn

[Jolly Roger VX'er]

My own personal experience has taught me that there was a double-edged sword involved with oil consumption in my engine.

The EGR Valve..if not properly recirculating exhaust gases back into the cylinders to be reburned (EGR=Exhaust Gas Recirculation) under normal operation, would lead to higher cylinder temps. Just like if you were to block it off and deny proper operation.

When the EGR is functioning properly, it is "smothering" the cylinders with spent exhaust gas that is meant to be reburned for environmental sake and therefore not letting in a totally fresh air/fuel mixture during the intake stroke. In effect...it is lowering the efficiency of each cylinder. Make the EGR inoperable either through failure (ie.stuck closed) or physically blocking it off and the cylinder temps go up due to the more efficient combustion of a fresh air/fuel intake charge not being smothered by exhaust gasses fed into the cylinders through the intake by the EGR.

Then...add in a malfunctioning PCV which leads to high crankcase pressure that "resists" the oil in the cylinder attempting to return back to the oil pan.

Now that you have oil lingering around in the cylinders due to opposing pressure of a stuck PCV and higher cylinder temps due to a stuck EGR you get alot of oil burn-off during the combustion process.

In short...My VX started using oil before I supercharged it at 30,000 miles; and after I cleaned out the EGR with oxgen sensor safe carb cleaner to remove the black carbon that was causing it to stick closed....and after I started changing the PCV at regular intervals to maintain proper operation....the oil usage dropped drastically to what I consider normal (approx. 1/4 quart in 3,000 mile oil change interval....sometimes less)

I recommend cleaning the EGR @ 30,000 mile intervals...or replacing it if cleaning it doesn't free up a stuck valve. I recommend maintaining proper operation of the PCV.

If there is an oil ring problem..it will only be exaggerated by the failures of either the EGR and/or the PCV systems....think of all this as a triangle...where you have control over 2 of the 3 legs.

[Gussie2000]

My own personal experience has taught me that there was a double-edged sword involved with oil consumption in my engine.

The EGR Valve..if not properly recirculating exhaust gases back into the cylinders to be reburned (EGR=Exhaust Gas Recirculation) under normal operation, would lead to higher cylinder temps. Just like if you were to block it off and deny proper operation.

When the EGR is functioning properly, it is "smothering" the cylinders with spent exhaust gas that is meant to be reburned for environmental sake and therefore not letting in a totally fresh air/fuel mixture during the intake stroke. In effect...it is lowering the efficiency of each cylinder. Make the EGR inoperable either through failure (ie.stuck closed) or physically blocking it off and the cylinder temps go up due to the more efficient combustion of a fresh air/fuel intake charge not being smothered by exhaust gasses fed into the cylinders through the intake by the EGR.

Then...add in a malfunctioning PCV which leads to high crankcase pressure that "resists" the oil in the cylinder attempting to return back to the oil pan.

Now that you have oil lingering around in the cylinders due to opposing pressure of a stuck PCV and higher cylinder temps due to a stuck EGR you get alot of oil burn-off during the combustion process.

In short...My VX started using oil before I supercharged it at 30,000 miles; and after I cleaned out the EGR with oxgen sensor safe carb cleaner to remove the black carbon that was causing it to stick closed....and after I started changing the PCV at regular intervals to maintain proper operation....the oil usage dropped drastically to what I consider normal (approx. 1/4 quart in 3,000 mile oil change interval....sometimes less)

I recommend cleaning the EGR @ 30,000 mile intervals...or replacing it if cleaning it doesn't free up a stuck valve. I recommend maintaining proper operation of the PCV.

If there is an oil ring problem..it will only be exaggerated by the failures of either the EGR and/or the PCV systems....think of all this as a triangle...where you have control over 2 of the 3 legs.

I got to agree with you about this one,my mech told the same thing as you explained here.

The PCV should be replace every oil change just for the sake of the engine.

In february i'll have my VX's transmission,transfer case & differential fluids serviced & i'll probally have the EGR cleaned so make sure full performance is delivered

[psychos2]

I got to agree with you about this one,my mech told the same thing as you explained here.

The PCV should be replace every oil change just for the sake of the engine.

This is all good as long as the pcv valve functions properly for 3000 miles. I had a brand new one malfunction and lost 2 qts of oil in the first 1000 miles After an oil change and pcv valve change. If I had not checked the oil level before leaving on a 3 hr trip to NH I would have had a seized motor.

Also I would have to disagree with this statement:
"Then...add in a malfunctioning PCV which leads to high crankcase pressure that "resists" the oil in the cylinder attempting to return back to the oil pan.

Now that you have oil lingering around in the cylinders due to opposing pressure of a stuck PCV and higher cylinder temps due to a stuck EGR you get alot of oil burn-off during the combustion process."

There should be no oil in the cylinder trying to return to the pan. Any oil that gets past the rings or is sucked in through the pcv valve will not return to the oil pan it gets burned. Or do you mean the oil in the crankcase below the piston on the cylinder wall ? shawn

[Jolly Roger VX'er]

There should be no oil in the cylinder trying to return to the pan. Any oil that gets past the rings or is sucked in through the pcv valve will not return to the oil pan it gets burned. Or do you mean the oil in the crankcase below the piston on the cylinder wall ? shawn

Absolutely true...if excessive enough gives you the tell-tell bluish smoke out the exhaust pipe (worn rings)

Yes, I was meaning the oil in the crankcase below the piston on the cylinder wall that could be opposed by high crankcase pressure to return to the pan and be subjected to the high volitility (burn-off) of elevated cylinder temps due to malfunctioning EGR. Sorry, I should have stated it better than I did.

[Jolly Roger VX'er]

This has been a presentation of "Your internal combustion engine & you, the early years"...

ouch...your making me experience flash-backs of a black & white 8mm tape reel movie on an old projector with some monotone sounding guy chirping away making my eyelids real droo---oooo---pppie...zzzzzzzzzzzzzzzzzz