Burning Oil?

[Ikkesh]

Is it Normal to be adding a quart of oil a month into my VX?

No Blue Smoke, No Leaks, Where's It Going?


Ideas?

[JoFotoz]

Yes ...and No....:o

Depends on your mileage.....which ya dont state.



Give up some info...

jo

[Ikkesh]

128,000 miles

I baught it used, I Just wish i knew who used to own it to find out service info on it.

[ScottinMA]

The point is...how many miles do you drive before before adding a quart?

[Ikkesh]

1 quart For every 3 Fillups I think.

[Ldub]

Not to be too much of an alarmist, but...:sighwgray

This particular motor (and some say 99's in particular), tends to use oil.
The oil level should be checked at every fill up & the PCV valve ($3-5.00), should be changed every other oil change.
The result of not staying on top of your oil level, is motor replacement, no if's, and's or but's...:eek:

Use the handy search function using "oil consumption" for more...:thumbup:

Welcome to the Fam...:cool:

[Scott Harness]

99- 118,000 miles, used to burn 1quart every 1200 miles,NOW every 500 miles:eek: I've got to get a ring job before Moab. Runs fine,I just have to really watch it.

[Gussie2000]

Oh man,believe me,you're not alone with this one if that makes you feel better.

I bought mines with only 38,780 miles last year around november,my odo reads 45,869 right now & it do burns oil,i drives the average of 15 miles per day;Full syntetic is the key to an longlasting engine (mobile 1 or amsoil),don't abuse it,use 5w-30 on cold weather & 10w-30 on summer. Don't play with this one.

My mechanic who's an former isuzu engine specialist told me that isuzu engineers oversight the facts that the ducts the oil runs throughtout the engine were too big & too few of them so a considareble amount of oil goes into the combustion chamber which shouldn't be happening,specially on high RPM's situations such as be in the highway or express ways when the oil pump pumps high amounts of oil as per demanded by the engine.

Isuzu knows about this issue,but's financially high the amount of money they would had to put out here in order to have that issue solve,which in fact is that isuzu will had to redesign the whole engine or build a new one for each VX,rodeo,axiom,amigo & trooper on the streets so they best move is to ignore the issue,so clever don't they ?

This problem is found in almost all 1998 to 2001 engines my mech told me,he had more that 200 isuzu troopers,rodeos & 2001 axioms just in his shop & about 3 vehicross (included mines) which had a few sticky lifters due the lack of use.

In 2002 isuzu overcome this issue with they new engine.

If you have the meanings $$$$ & if the vehicross means a lot for you,plus the value the VX will have over there & the overall conditions of your VX you should dropped an 2002 isuzu axiom engine with the less mileage you can possible find into it if isuzu had axioms for sale there.

The 2002 engine fits perfectly without any more mods,is like a plug & play stuff.

Plus this engine is more powerfull it comes with 230 HP instead of the 215.

Rebuilt is another option,but the oil conpsumtion can be back again,problally with less amount of loss oil.

When i got aknowledge about this issue my thoughts were : DAMN I SCREW UP,but after a found that many VX's made the 100,000 & + miles i believe mines can go that far as yours.

One of my co-workers have a 2002 rodeo with more then 200,000 miles on the clock & that bastard runs like an champion.

The secret : maintainance,that's all about he says,don't abuse it,just drive as you should drive an vehicule.

[99VC]

I guess I must be lucky with my 99 with 102,689 miles, I drove it up to Vail Colorado from Las Vegas over 650 miles and didn't burn a drop......

[VCrossfan]

Nice info Gussie ! ! :fyi::thumbup:

[Ikkesh]

Heh was begining to think my Vehicross was "Retarted" err... I mean "Not Normal".

knowing this makes me feel better about my pourchase.

Paid $8,500 for mine
All I use is Synthetic Mobil One

I Just hope the Previous Owner Knew Enough to top his engine oil off under these circumstances!

My Mechanic said Comression is good Mechanichally everything is sound aside from that the only things triggering the Check Engine Light was the Gas Cap and MAF Sensor (of which I cleaned) and Gas Cap Replaced..

Strange though, Check Engine Light Went Back On a Week Ago After resolving those issues!

Got an Apt For Timing Belt, And Waterpump Just waiting for OEM Belt to get here. I heard to Use the OEM Timing Belt Due to Isuzu Warrants the Vavles if Belt Fails....

we shall see.

[nfpgasmask]

Join the club, I've been a burner since 30k...

Bart

[etlsport]

Heh was begining to think my Vehicross was "Retarted" err... I mean "Not Normal".

knowing this makes me feel better about my pourchase.

Paid $8,500 for mine
All I use is Synthetic Mobil One

I Just hope the Previous Owner Knew Enough to top his engine oil off under these circumstances!

My Mechanic said Comression is good Mechanichally everything is sound aside from that the only things triggering the Check Engine Light was the Gas Cap and MAF Sensor (of which I cleaned) and Gas Cap Replaced..

Strange though, Check Engine Light Went Back On a Week Ago After resolving those issues!

Got an Apt For Timing Belt, And Waterpump Just waiting for OEM Belt to get here. I heard to Use the OEM Timing Belt Due to Isuzu Warrants the Vavles if Belt Fails....

we shall see.

unless you bought your VX new from a dealer or bought from a family member who was the original owner.. your VX is out of warranty:( they had 10 year 120k mile warranties in 00 and 01.. which cut in half upon sale to a non-family member

as for the check engine light.. what is the code? a lot of people have issues with their EGR valve causing check engine lights but iirc the code doesnt necessarily reflect that thats the problem... also when replacing the timing belt.. look around there are a few TSBs (technical service bulletins) that correct the timing belt replacement procedure as well as the torque on the intake manifold (the intake manifold gaskets might be leaking due to a mistake in torquing the bolts.. that could cause a check engine light too)

oh and i burn about 1 quart every 3k miles using mobil 1 synthetic.. but it all happens fast.. like i will be fine for 1000-2000 miles then all of a sudden 500 miles and ill be 1/2 quart low.. i just check every gas fillup and keep a bottle of oil on hand so that i can keep it right on the full mark at all times.. if you pay close attention you can spot warning signs.. im to the point where i swear i can hear when my VX is running low on oil

[Gussie2000]

unless you bought your VX new from a dealer or bought from a family member who was the original owner.. your VX is out of warranty:( they had 10 year 120k mile warranties in 00 and 01.. which cut in half upon sale to a non-family member

as for the check engine light.. what is the code? a lot of people have issues with their EGR valve causing check engine lights but iirc the code doesnt necessarily reflect that thats the problem... also when replacing the timing belt.. look around there are a few TSBs (technical service bulletins) that correct the timing belt replacement procedure as well as the torque on the intake manifold (the intake manifold gaskets might be leaking due to a mistake in torquing the bolts.. that could cause a check engine light too)

oh and i burn about 1 quart every 3k miles using mobil 1 synthetic.. but it all happens fast.. like i will be fine for 1000-2000 miles then all of a sudden 500 miles and ill be 1/2 quart low.. i just check every gas fillup and keep a bottle of oil on hand so that i can keep it right on the full mark at all times.. if you pay close attention you can spot warning signs.. im to the point where i swear i can hear when my VX is running low on oil

I guess you do eric.

My mechanic told me the 1srt time i had the VX serviced that isuzu shall had built a specific engine for the VX,some sort of 3.7 to 4.0L,even though this 3.5L engine is a high tech he said that the weight-acceleration-speed-HP is just not completly right.
For his weight the VX should be propelled by at least 250 HP with a 280 PSI torque force which will make the VX way more powerfull & faster.

Isuzu probes that they are capable to build excelents SUV's,the fact that the VX won the paris-to-dakar rally twice over more powerfull SUV's with the 3.5L engine is an indication that isuzu knows they stuff.

But again,isuzu didn't had intentions to mass produce the VX so they figure out they'll not invest much of money building a exclusive engine,like how the jeep did with the grand cherokee SRT-8 with the 6.1L plus they were already in financial "recesion" so even though they wanted too they wouldn't be able to afford it :(

And i believe what he said because you can see right now powerfull SUV's such as the acura MDX with the same weight & propelled by an 280 HP engine,the jeep liberty with an 3.7L & 260 HP & the infiniti FX 35 with 300 HP

What makes the difference with our VX's is the 230 PSI torque at 3000 RPM he add.

If isuzu did dropped in an 3.7 or 4.0 L the VX will the most powerfull two-doors SUV on the planet :cool:

[VehiGAZ]

Heh was begining to think my Vehicross was "Retarted" err... I mean "Not Normal".

knowing this makes me feel better about my pourchase.

Paid $8,500 for mine
All I use is Synthetic Mobil One

I Just hope the Previous Owner Knew Enough to top his engine oil off under these circumstances!

My Mechanic said Comression is good Mechanichally everything is sound aside from that the only things triggering the Check Engine Light was the Gas Cap and MAF Sensor (of which I cleaned) and Gas Cap Replaced..

Strange though, Check Engine Light Went Back On a Week Ago After resolving those issues!

Got an Apt For Timing Belt, And Waterpump Just waiting for OEM Belt to get here. I heard to Use the OEM Timing Belt Due to Isuzu Warrants the Vavles if Belt Fails....

we shall see.

+1 on your oil burning issue - very common. I would suggest to stop using synthetic oil if you are burning it at that rate - the synthetic is great if the engine doesn't burn it, but it's doing you no good to put super-expensive synthetic if it's going to go up in smoke (so to speak) before it needs replacing.

If you have a K&N style oiled air filter, that might be the cause of your CE light. The oil fouls the MAF, so you either have to keep cleaning it or go back to the OEM filter (which a team of engineers decided was perfectly adequate).

Good luck!

[nfpgasmask]

Another opinion here, if you are getting a CEL, I would try to get the code read so you know what the issue is. It could very easily be a stuck EGR valve....

Bart

[Jolly Roger VX'er]

the PCV valve ($3-5.00), should be changed every other oil change.


I was following this advice until I went to Moab & a brand new PCV failed. Second time this has happened to me...first time with AutoZone brand. I took out a perfectly good one before the road trip and put in a new one only to have it (the new one from Advance Auto--Purolator) stick closed.

My engine which usually is very good on oil usage (like 1/4 quart in 3,000 miles) sucked up one quart out of the blue. Caught it when I refueled & checked oil. Than saw oil spray coming out of my breather cap (aftermarket).

My new approach is to just leave a functioning one in and check periodically for any oil spray from breather cap & check dipstick @ fuel stops plus when putzing under the hood. It looks like my set-up allows the excess crankcase pressure to exit out the breather cap (if PCV is stuck) when normally it would be sucking air into the breather cap. I'll carry a spare PCV from now on and be reactive instead of proactive!

[Ldub]

I was following this advice until I went to Moab & a brand new PCV failed. Second time this has happened to me...first time with AutoZone brand. I took out a perfectly good one before the road trip and put in a new one only to have it (the new one from Advance Auto--Purolator) stick closed.

My engine which usually is very good on oil usage (like 1/4 quart in 3,000 miles) sucked up one quart out of the blue. Caught it when I refueled & checked oil. Than saw oil spray coming out of my breather cap (aftermarket).

My new approach is to just leave a functioning one in and check periodically for any oil spray from breather cap & check dipstick @ fuel stops plus when putzing under the hood. It looks like my set-up allows the excess crankcase pressure to exit out the breather cap (if PCV is stuck) when normally it would be sucking air into the breather cap. I'll carry a spare PCV from now on and be reactive instead of proactive!

Good point, I've had a purolator seperate before (top & bottom came apart), but I still like em', IMO, there will be occaisional defects in any brand.

Another thing you can do, is clean em' out with carb/TB cleaner & keep em' as a spare.

[psychos2]

My mechanic who's an former isuzu engine specialist told me that isuzu engineers oversight the facts that the ducts the oil runs throughtout the engine were too big & too few of them so a considareble amount of oil goes into the combustion chamber which shouldn't be happening,specially on high RPM's situations such as be in the highway or express ways when the oil pump pumps high amounts of oil as per demanded by the engine.

This problem is found in almost all 1998 to 2001 engines my mech told me,he had more that 200 isuzu troopers,rodeos & 2001 axioms just in his shop & about 3 vehicross (included mines) which had a few sticky lifters due the lack of use.



1st , most of the oil consumption issues are pcv valve related. There is no baffle in the valve cover to keep the oil away from the pcv valve and when it sticks open the oil is sucked into the intake and burned. Has nothing to do with oil passages. Had it happen to me I was using 1 qt per 3000 miles ,when the pcv valve stuck I used 2 qts in 1000 miles. I no longer have a pcv valve. back to 1 qt per 3000 miles.And no worries about when it the pcv valve will stick again.

2nd ,there is no way any vx with a 3.5 has stuck lifters. they do not have any. They have the camshaft in the head directly above the valves, I believe it is called a direct attack setup. No lifters ,no rocker arms.

also in 2002 they came out with the direct injection 3.5 which has more hp because the fuel is injected directly into the cylinders. I believe this engine is not a direct swap and you would have to change the wiring harness and computer.
I am in no way trying to start anything just correcting incorrect info. shawn

[Jolly Roger VX'er]

Good point, I've had a purolator seperate before (top & bottom came apart), but I still like em', IMO, there will be occaisional defects in any brand.

Another thing you can do, is clean em' out with carb/TB cleaner & keep em' as a spare.


I still have the one I bought in Moab (like $12...ouch...but if it lasts it was worth it!!!!) that was a brand I never heard of (sold at one of those Mom & Pop Parts stores!) and it works like a champ..rattles properly when checked...no problems! I figure I'll just keep an eye on it.

Plus, I did have good luck with the PCV sold @ NAPA in the past, but only used that brand twice. It was made in USA and cost like $8.

I still remember the old days..lol..I had a '69 Plymouth Roadrunner and the only pollution control was a PCV...and it was made out of stamped steel with a steel ball bearing inside...NOW that sucker was good for 40+ years I'd bet!!!!!!!

[Ldub]

I still have the one I bought in Moab (like $12...ouch...but if it lasts it was worth it!!!!) that was a brand I never heard of (sold at one of those Mom & Pop Parts stores!) and it works like a champ..rattles properly when checked...no problems! I figure I'll just keep an eye on it.

Plus, I did have good luck with the PCV sold @ NAPA in the past, but only used that brand twice. It was made in USA and cost like $8.

I still remember the old days..lol..I had a '69 Plymouth Roadrunner and the only pollution control was a PCV...and it was made out of stamped steel with a steel ball bearing inside...NOW that sucker was good for 40+ years I'd bet!!!!!!!

I was thinkin' the same thing...except get one machined out of SS or aluminium, with top & bottom halves threaded together so you could take it apart to clean...:_wrench:
Would last forever & co$t big bucks by comparison...a guy can dream, yah?
I miss my 70 Mustang...wasn't a "Boss" but had all the boss spoilers, rear window louver, paint scheme, ET's, Lakewood...yadda-yadda-yadda...:cool:
Can't even find a pic of it any more...:sighwgray

[BigSwede]

While I do think some of the oil burning is PCV related, there is another theory than the several presented here - this is what Jerry Lemond, who used to train Isuzu mechanics, told me:

The 3.5L is a stroked version of the 3.2L. Because of the deeper crankshaft necessary for the 3.5L, the pistons had to have relatively short skirts to avoid impacting the crankshaft, leaving less room for piston rings. As a result the 3.5L pistons only have one oil ring. The oil ring's job is to squeegee oil from the cylinder wall. The oil ring also has drain-back holes for any oil that gets trapped between the oil ring and the compression ring. The oil ring for the 3.5L only had 4 drainback holes, which apparently was inadequate for the job, so some of the trapped oil ends up going the other way, up into the combustion chamber and is burned.

The improved design 3.5L, identifiable by the screw-in PCV valve, has oil rings with additional drainback holes.

[shrug] I dunno which theory or combination thereof is correct, just thought I'd pass this one along. Have a nice day :)

[VehiGAZ]

ONE ring on each piston?!?! Can anyone confirm that?!

That would be enough to lead to oil burning as soon as the one, lonely ring loses it's state of perfection...

[psychos2]

While I do think some of the oil burning is PCV related, there is another theory than the several presented here - this is what Jerry Lemond, who used to train Isuzu mechanics, told me:

The 3.5L is a stroked version of the 3.2L. Because of the deeper crankshaft necessary for the 3.5L, the pistons had to have relatively short skirts to avoid impacting the crankshaft, leaving less room for piston rings. As a result the 3.5L pistons only have one oil ring. The oil ring's job is to squeegee oil from the cylinder wall. The oil ring also has drain-back holes for any oil that gets trapped between the oil ring and the compression ring. The oil ring for the 3.5L only had 4 drainback holes, which apparently was inadequate for the job, so some of the trapped oil ends up going the other way, up into the combustion chamber and is burned.

The improved design 3.5L, identifiable by the screw-in PCV valve, has oil rings with additional drainback holes.

[shrug] I dunno which theory or combination thereof is correct, just thought I'd pass this one along. Have a nice day :)

The pistons have 3 rings like any other piston. And the theory about the drain back holes would be ok if all 3.5L engines had the same oil consumption amount. shawn

[JHarris1385]

Here is my repost on this issue:

Hi John,

Its not actually oil loss that’s a problem its oil pressure loss. Where the oil filter bolts onto the engine you will see that it does not bolt directly to the block. It bolts onto a cast metal item which is attached to the block. This cast piece that sits between the block and the oil filter is one of the main problems of oil pressure loss. Inside it there is very sharp bends which restricts oil flow and therefore oil pressure.

We solve this issue by removing this cast piece and have it replaced with another fitting that allows the oil filter to be remote mounted. This will be available for purchase shortly.

The other issue is only when the engine is pulled down. The oil feed system to the main bearings comes in at the number 1 piston and travels along feeding the others. This means that the number 6 piston is the last one to get any oil fed to it and is why the number 6 bearing is prone to failure. We have a modified oil delivery system available which rectifies this problem and gives even oil flow and pressure to all main bearings.

[Gussie2000]

While I do think some of the oil burning is PCV related, there is another theory than the several presented here - this is what Jerry Lemond, who used to train Isuzu mechanics, told me:

The 3.5L is a stroked version of the 3.2L. Because of the deeper crankshaft necessary for the 3.5L, the pistons had to have relatively short skirts to avoid impacting the crankshaft, leaving less room for piston rings. As a result the 3.5L pistons only have one oil ring. The oil ring's job is to squeegee oil from the cylinder wall. The oil ring also has drain-back holes for any oil that gets trapped between the oil ring and the compression ring. The oil ring for the 3.5L only had 4 drainback holes, which apparently was inadequate for the job, so some of the trapped oil ends up going the other way, up into the combustion chamber and is burned.

The improved design 3.5L, identifiable by the screw-in PCV valve, has oil rings with additional drainback holes.

[shrug] I dunno which theory or combination thereof is correct, just thought I'd pass this one along. Have a nice day :)

Thank you !

[Gussie2000]

1st , most of the oil consumption issues are pcv valve related. There is no baffle in the valve cover to keep the oil away from the pcv valve and when it sticks open the oil is sucked into the intake and burned. Has nothing to do with oil passages. Had it happen to me I was using 1 qt per 3000 miles ,when the pcv valve stuck I used 2 qts in 1000 miles. I no longer have a pcv valve. back to 1 qt per 3000 miles.And no worries about when it the pcv valve will stick again.

2nd ,there is no way any vx with a 3.5 has stuck lifters. they do not have any. They have the camshaft in the head directly above the valves, I believe it is called a direct attack setup. No lifters ,no rocker arms.

also in 2002 they came out with the direct injection 3.5 which has more hp because the fuel is injected directly into the cylinders. I believe this engine is not a direct swap and you would have to change the wiring harness and computer.
I am in no way trying to start anything just correcting incorrect info. shawn

By the way i replace the PC valve the day i had my VX oil change the 1rst time,still oil compsumtion keeps happening,so no,oils goes into the combustion chamber & burn,the piston rings were manufactured with wrong specs,that's exactly what the mech was explaining me;I'll print your intup & take it to him so let's see who could be wrong.

[psychos2]

By the way i replace the PC valve the day i had my VX oil change the 1rst time,still oil compsumtion keeps happening,so no,oils goes into the combustion chamber & burn,the piston rings were manufactured with wrong specs,that's exactly what the mech was explaining me;I'll print your intup & take it to him so let's see who could be wrong.

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

[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...:_wrench:

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

[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.

[Jolly Roger VX'er]

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


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:snooz:

[BigSwede]

The pistons have 3 rings like any other piston. And the theory about the drain back holes would be ok if all 3.5L engines had the same oil consumption amount. shawn
You may be right about the number of rings, I wasn't sure about that part and was going from memory of a conversation over a year ago. But the change in oil ring drainback holes is the main point and is factual. Whether it is the main cause of oil burning is another question.

I also meant to say there is an oil-burning connection with the EGR system more so than PCV. My old 99 Trooper didn't burn any oil (at least until it got totaled), which I suspected had to do with the Mobil One I used and it's tendency not to gum up the EGR system. But I have no way to prove it.

[BigSwede]

ONE ring on each piston?!?! Can anyone confirm that?!

That would be enough to lead to oil burning as soon as the one, lonely ring loses it's state of perfection...
No, I was saying one oil ring, which still would be in addition to the compression ring. But as was noted there are indeed 3 rings not just 2.

[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

[iamironman]

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Done!!






--------

[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.

[ilya]

Hi, car guy here, has anyone put in aftermarket pistons or tried to swap in the newer style piston from the 02 or 04 engine in hopes of solving this?

[Gussie2000]

Hi, car guy here, has anyone put in aftermarket pistons or tried to swap in the newer style piston from the 02 or 04 engine in hopes of solving this?

HI Ilya !

Absolutely ! many VX'ers had their engines rebuildt or completly replaced.

I personally have no idea if aftermarket rings is a good deal to go for,however i'll suggest you to do some research & figured out two tips:


COST AGAINS VALUE AGAINS QUALITY

If a set of original OEM pistons from isuzu cost $ 350 & the aftermarket set cost $ 280 i'll try to put the other $ 70 & buy the original .....This is my quote

[kodiak]

As far as I know it’s not the pistons or rings that’s causing the oil consumption problem. :confused:


Hi, car guy here, has anyone put in aftermarket pistons or tried to swap in the newer style piston from the 02 or 04 engine in hopes of solving this?

[TheGanzman]

As far as I know it’s not the pistons or rings that’s causing the oil consumption problem. :confused:


http://www.isuzuforums.com/forum_posts.asp?TID=1877

[Junster]

Hoping for an answer to the "rebuild using 2002/04 pistons and rings" any info on this? I have fallen off the deep edge and will have a VX soon. I tend to keep a vehicle a long time. So a engine rebuild is almost always somewhere in it's future. Thanks

[VX KAT]

Hoping for an answer to the "rebuild using 2002/04 pistons and rings" any info on this? I have fallen off the deep edge and will have a VX soon. I tend to keep a vehicle a long time. So a engine rebuild is almost always somewhere in it's future. Thanks


Here's several threads on oil consumption, theories of what causes the problem, engine failure, polls, experience, etc... Might help you decide on whether it's the pistons, or better to rebuild or replace with an Axiom engine.

Several theories on Isuzu design defect in rings that causes oil consumption:
http://www.vehicross.info/forums/showthread.php?t=14548&highlight=brand+pcv+valve

http://vehicross.info/forums/showthread.php?t=3756&highlight=ENGINE+FAILURE+POLL

http://vehicross.info/forums/showthread.php?t=16854&highlight=ENGINE+FAILURE+POLL

http://vehicross.info/forums/showthread.php?t=17228&highlight=engine+oil+poll

http://vehicross.info/forums/showthread.php?p=166184#post166184

http://www.vehicross.info/forums/showthread.php?t=15156&highlight=axiom+DI

http://www.vehicross.info/forums/showthread.php?t=16136&highlight=axiom+DI

http://vehicross.info/forums/showthread.php?t=14775&highlight=iamironman

Here's the thread from Iamironman...
http://www.vehicross.info/forums/showthread.php?t=16157&highlight=built+2000

http://www.vehicross.info/forums/showthread.php?t=15156&highlight=engine+swap+axiom


__________________

[IndianaVX]

Just putting this out there. When I had my valve covers off, I did notice a "plate" seperAting the pcv valve from the rest of the heads. In other words, if you take the pcv valve out, poke a screwdriver down the hole, you will hit this plate, not the cams. The plAte is screwed to the top, on the inside of the covers.
Don't know what that all means, but it's something that's there, and I thought it WAS a baffel.