[FJoel]

That engine is toast...You can't fix sludge.

Care to elaborate?

:lol:

 

[Rust86]

I'm inclinder to agree with kciaccio. Engine sludge can't be removed and its likely that more problems are in store for that engine.

As a side note I work at a japanese repair shop and looked up the 07 fj on identifix. ( 07 is same year as mine)

the second most common search on that vehicle is p0016. long story short is once you've confirmed that its not a cam or crank sensor and not the vvt oil control valve. Its going to be the chain. P0016 is a correlation code. meaning the camshaft is not where it is supposed to be when it's supposed to be. I've never seen a chain stretched enough to throw a code on a 4.0 yet but I've seen it many times on undermaintained nissans and hondas. Saying your engine was undermaintained doesn't even come close to doing it justice.

If that engine were in my shop I would be condemning it. You on the other had have "free" labor you can put into it so cost effectiveness doesn't have to factor in.

If I were you I'd throw new chains on it. make sure you flush out the cam adjuster really really good and throw it back together to see what happens.
---
Now if I were me (in your situation) and I had already planned on putting a v8 in it. I'd quit while I was ahead. That engine has no value as a used part cause someone would have to be nuts to pay money for an engine that is that sludged so even if you get the code gone you'd be doing someone a disservice by selling them that engine.
---
Lastly, I admire your tenacity and have to say you have been going about the diagnostic process very intelligently. very good work!

 

[FJoel]

There is a lot of snake oil on the market, but I've seen a few crankcases get cleaned up with either some ATF fluid added to the oil, or Marvel Mystery Oil.

I don't recommend leaving either of those products in your oil, but if you add either before an oil change, drive around for while at operating temperature, and dump the oil, guaranteed there will be less sludge in the engine than before. I've seen it with my own 2 eyes, on several engines, where the cylinders are quite easily removed from the crankcase (I like hanging out at airports).

Perhaps my definition of sludge vs. varnish is different than some of yours. I also believe that the quality of the gasoline has a lot to do with sludge and varnish build up, as any impurities, when burned, create different, unwanted by-products.

On engines that run a lot, at 75% to 100% power for most of their life, and get overhauled between 1800 and 2000 hours, I've personally seen a difference in identical models of engines based on the quality of the gasoline used versus the amount of sludge they had in them.

I don't quite buy it when you say you can't fix sludge.

It's really not hard to regularly change your oil though, and inexpensive to boot. Sucks to see an engine like this that was clearly under-maintained.

On the other hand, my engine has been pretty well looked after with more oil changes than are probably needed with the Amsoil I use, and it still has issues too.

 

[ZUNAMI1]

Dude I think it may just be a loose chain, when an engine jumps time trust me you know it. Given the length of the chain it wouldn't take very much stretch to retard the timing on the top side.

You maybe right. It may be just stretch but if I realign the timing by turning back a tooth it appears timing would be back in sync. You have to consider also I will not spend the money or effort to replace the chain. I bought this FJ to do a V8 and drive train swap. Right now it looks to be a full tooth off which is interesting to me. It is quite easy to get the point I'm at which is valve covers off and tensioner removed. Much easier than I thought. Now turning the crank pulley back a tooth is the trick. If it works timing chain replacement or a timing chain roll back is the answer for some experiencing the same problem. I have other cars to drive while I fiddle or I would have spent the weekend replacing the chain, the proper thing to do for an other wise good running and driving FJ.

If I do get to a point where the engine is out and front cover comes off I will be able to see and line up original, painted install links and that will tell the story of stretch or skip.

Also, the tensioner is not fully extended. I would expect more extension from a badly stretched chain and worn guide. Remember, the two banks appear to be in sync. Only the crank appears out and it is way out so the banks should be out proportionally.

Thanks for chiming in.

 

[ZUNAMI1]

I'm inclinder to agree with kciaccio. Engine sludge can't be removed and its likely that more problems are in store for that engine.

As a side note I work at a japanese repair shop and looked up the 07 fj on identifix. ( 07 is same year as mine)

the second most common search on that vehicle is p0016. long story short is once you've confirmed that its not a cam or crank sensor and not the vvt oil control valve. Its going to be the chain. P0016 is a correlation code. meaning the camshaft is not where it is supposed to be when it's supposed to be. I've never seen a chain stretched enough to throw a code on a 4.0 yet but I've seen it many times on undermaintained nissans and hondas. Saying your engine was undermaintained doesn't even come close to doing it justice.

If that engine were in my shop I would be condemning it. You on the other had have "free" labor you can put into it so cost effectiveness doesn't have to factor in.

If I were you I'd throw new chains on it. make sure you flush out the cam adjuster really really good and throw it back together to see what happens.
---
Now if I were me (in your situation) and I had already planned on putting a v8 in it. I'd quit while I was ahead. That engine has no value as a used part cause someone would have to be nuts to pay money for an engine that is that sludged so even if you get the code gone you'd be doing someone a disservice by selling them that engine.
---
Lastly, I admire your tenacity and have to say you have been going about the diagnostic process very intelligently. very good work!

Thanks for the advice. This engine is definitely not worth throwing labor dollars at. I think it is worth a chain under ordinary circumstances for a DIYer. I just want a V fricken' 8.

 

[ZUNAMI1]

another member asked in a private message: "i have this error code for the last 2 years, so the only remedy is to open he engine and check the tensioner..? "

No. I am thinking tensioner is a possible cause for noise from chain slap or cause for chain skip. I would say if could be the cam adjuster which can be replaced with valve cover removal leaving the front of the engine in place. It could be timing chain which replacement is a lot more labor. I have taken the tension out and I do see the potential for the tensioner to collapse from sludging. I was able to collapse mine and it did not want to open back up because is was coated with carbon. I could see this tensioner causing problems at start up only or continually if for some reason the step lock sludged and failed. In this case of lock failing I would expect the collapse to occur at start up each time with lots of noise that may go away with warm up and oil pressure.

If I find out it is a skip tooth on timing chain or chain stretch I MAY be able to rotate back a tooth but I haven't tried to yet but looks promising in my case. Chain replacement should still be done at some near future date of course.

It could be oil control valve and cam position sensor which I think you tried. If you swap sensors from side to side it should start and run normally. No start means poorly installed sensor or bad sensor. I assume the error would follow bad sensor to bank 2 but I am not convinced of this. Error codes don't always follow logic and it may very well be that p0016 bank 1 error comes up for ALL timing errors.

I have tried to blow out potential sludging with air the oil passages going to oil control valves but the engine is remarkably clean where oil flows is under pressure. I think the ATF and SEA Foam would work for the problem of sludging of oil passages but the suggestion that sludge is the root of the problem is overstated. Sludge and wear are a result or evidence of poor maintenance, poor design, and extreme use.

I would say that if you just took off the just passenger valve cover, found timing marks on on cams and crank pulley to be aligned you could rule in or out the timing chain. The drivers side cover is more involved. Removing just the passenger valve cover reveals both timing chain issue and tensioner problem and is minimally invasive. Drivers side requires top intake manifold removal which is not so bad but retrospectively I could diagnose everything from passenger side.

The tensioner by itself can be inspected easily by just removing the inspection cover, 4 easily removed 10 mm bolts on front. You need a mirror or scope to get a good view. Remove and replace could be done too but I would be hesitant to try without the valve cover off. Again recommend valve cover removal.

Below is a better pictures of timing mark. The blue tick mark should be on 0 degree while passenger side cam and adjuster marks should line up with the indented (not raised bump) alignment mark.

http://i.imgur.com/yIwFf3W.jpg

 

[Rust86]

Anything else I could possibly say would likely be redundant because you've proven your understanding of whats involved.

I'm very much looking forward to your V8 build thread! Any idea what motor you'd be using?

 

[ZUNAMI1]

That engine is toast...You can't fix sludge.

I agree with your supposition. Sludge certainly has the potential to cause critical failure. Just not what I've seen in this case.

Sludge is like LDL Cholesterol. You don't want a lot of it but if managed it won't kill you. Subject is still alive to counter your position.

I think ATF and Sea Foam would possibly clear the arteries of these 4.0's and the sludge I am seeing is not terminal. I think you have a cause and effect relationship and it matters what the cause. Not all sludge to be considered equal.

Sludge from a badly worn engine should be expected. But imagine sludge from a design flaw. i.e. hot spots. The engine may reach expected life despite sludge. Sludge formed due to lack of proper maintenance schedule is symptomatic. The engine would fail from lack of proper maintence regarless of the presence of sludge.

I see this engine and I think is proves the resilience of the 4.0 and I'm impressed. All the moving parts seem somewhat immune to sludge collecting only harmlessy on static parts, critical oil passages remain clear and functional. If sludge killed engines this one would have been dead along time ago. I suspect the probability of a blocked passage increases with sludge, in general, but this stuff finds it way harmlessly to the pan in this case.

I think the discovery of sludge in a truly toasted engine is yet another story. Upon tear down you might conclude a lack of maintenance, when in actuality, the engine may have a ton of miles on it and the operator continued to drive a very tired and overworked motor creating sludge as it slowly dies. This sludge is created regardless of the maintenance. The engine was doomed from extended use beyond it expectancy. Chicken or the Egg scenario. Sludge is a bad sign but not Toast. There seems a symbiotic relationship with the design of the 1grfe 4.0.

 

[ZUNAMI1]

Anything else I could possibly say would likely be redundant because you've proven your understanding of whats involved.

I'm very much looking forward to your V8 build thread! Any idea what motor you'd be using?

Maybe you are artfully saying there is no hope for this V6.:wink

The V8 I had lined up was Toyota 4.7 donor Tundra rig that was a roll over. I passed on that particular rig due this one regaining oil pressure and now running fine. I really am hoping to find a QuickSandStorm for the project. I reside off a dirt road so Black is tough to live with.

4.7 being just a slight upgrade but great on the street for a daily driver. Sleeper style.

 

[FJtest]

Zunami, RUST86 -

I've been following the "P0016/cam chain stretch" saga for some time, and I'd like to add some thoughts and solicit your input. Part of my job function is performing failure analyses on electromechanical systems, so forgive me if this seems long-winded but sometimes a lot of detail is required to make sure that everyone has a common understanding of what's going on.

First, the ECM sets the P0016 DTC only for a very specific set of timing values representing the relative positions of the crankshaft angular position sensor ("crank sensor") and the camshaft angular position sensors ("cam sensors").

The cam sensor timing values are referenced to what Toyota calls the "VVT learning value". This is essentially a calibration "zero point", or mechanical reference point, linking the timing pulses from the crank sensor to the timing pulses from the cam sensors, at a commanded (but not verified) cam position..

According to the '07 FSM, here is how the VVT learning value is established (slightly re-worded for clarity):

"The ECM optimizes the valve timing by using the VVT (Variable Valve Timing) system to control the angular position of the intake valve camshafts. The VVT system includes the ECM, the Oil Control Valves, and the VVT actuators. The ECM sends a target duty-cycle control signal to the OCV. This control signal regulates the oil pressure supplied to the VVT actuator. The VT actuator can advance or retard the angular position ("timing") of the intake camshafts.

The EMC calibrates the intake valve timing by setting the intake camshaft to the to the most retarded angle while the engine is idling. The ECM closes the OCV to lock the cam in the retarded position. The ECM stores this value (the timing value between the crank sensor and the cam sensors) as the "VVT Learning Value".

When the difference between the target and the actual intake valve timing is 5 degrees CA (Crankshaft Angle) or less, the ECM stores that value.

If the VVT learning value matches the following conditions, the ECM determines the existence of a malfunction in the VVT system, and sets the DTC.

1. VVT learning value: less than 22.5CA, or more than 45.2 CA;
2. Above condition exists for 18 seconds or more.

This monitor runs every driving cycle, and turns the MIL on if the condition is present for two driving cycles (not specified if they must be consecutive driving cycles).

Now to digress a moment.

There are two timing systems in the '07-'09 1GR-FE engine:
1. The "fixed" timing between the crank sprocket and the cam sprockets. This fixed timing can only be affected by cam chain wear ("stretch"), or by the chain jumping a tooth on one or more sprockets. This timing relationship can be visually confirmed by pulling the timing cover and looking at the physical marks on the crank and cam sprockets. This will immediately confirm if the chain has jumped a tooth on any of the sprockets, or is severely worn.

2. The "variable" timing between the cam sprockets and the reluctor rings on the intake camshafts. This is the timing that is "adjustable" through the action of the VVT actuators.

I think that a possible weakness in this scheme is how the "learning" value is established, and the possible effect on triggering the P0016 DTC if the learning value drifts over time. This can be due to the inability of the VVT actuator to be driven to the "fully retarded" position because of debris buildup inside the actuator itself.

The timing values that trigger the DTC could be affected by timing drift in either or both of these systems.

The VVT actuators can act as pretty efficient "centrifugal oil filters", slinging out debris (sludge particles) and compacting them on the inner diameter of the actuator, exactly where they are swept and compacted by the moving-vane portion of the actuator. Over time, this material may get packed into a hard deposit that prevents the VVT actuator from reaching either the fully-retarded or fully-advanced positions.

Since it appears that the "VVT Learning Value" may be re-established with every engine start, is it possible that a slow drift in the Learning Value may eventually cause the crank/cam timing value to exceed the limits and trigger the DTC? It seems like a combination of conditions in a heavily-sludged engine could all contribute to this failure mode:

1. Low engine oil pressure not providing enough force to drive VVT actuators to fully retarded position;
2. Sludge/debris buildup in VVT actuator physically preventing VVT actuator from reaching the fully retarded position;
3. Restriction in oil passages to oil control valves causing further pressure drop contributing to #1 ;
4. Contamination or heavy varnish causing less-than-full-opening of oil control valves contributing to #1 .


It seems like the potential for this occurring would be much greater with a heavily sludged engine.

I think it might be very interesting to simply open the VVT actuators before doing anything else that might affect crank/cam timing, and see if there is any debris in the oil chambers that might limit the ability of the rotor to physically reach the fully-retarded (counterclockwise) position.

Bear in mind that this engine has an oil jet that is intended to spray oil directly on the cam chain just before it wraps around the crank sprocket, and in a heavily-sludged engine this jet might become restricted or even totally blocked, eventually resulting in excessive chain wear.

Any thoughts/comments comments are appreciated.

 

[ZUNAMI1]

To reply to above. First, thank you for the contribution. Nice technical read.
I have been able to evaluate the cam adjusters with the tensioner removed. With the chain slack you can rotate the cams counterclockwise. The lock pins can be felt and heard "caming out" of locked position. They sound like a snap of metal on metal from spring loaded lock pin. They sound sharp and clean. I would expect that area to be especially gummed up with sludge and give a dull, sluggish sound if mucked up. It rotates off the lock with a slight bump stop at full retard. I was hopeful to find some sluggish, gummy feeling from these, but no. Upon inspection, mechanically, they sound good, rotate without indication of resistance or friction of any significance.
In the pictures, I show the valve covers with some treated sludge. At room temp the ATF and Sea Foam both liquify the sludge into flow-able coffee ground substance that feels light moist cookie crumbs. All for the sludge was ashy and fragile. Nothing stone hard. I did treat the engine with both before cracking open the covers and this may have cleaned passages a bit. The stuff does appear to be effective in pressurized areas. I strongly believe that things were flowing clear and clean where pressure was present.

The oil control valve return spring in pictures show clogging and sludging. They moved effortlessly when manipulated with a screwdriver and the build up in the picture seemed to have not effect. The dirty oil valves were fine. The new valve was comparable in range of motion to old valve and in examination there appeared to be zero issue with function. Again with sludge present I was leaning hard toward ocv. Covers off, clearly skip tooth or stretch amounting to 10 degrees at the crank.

I could barely scope the oil valve passages. Remarkably clean. Again the areas of pressurized oil circulation are all clean.

The heads have oil reservoirs that did collect sludge as they are just "cups" cast into the heads. They still contained oil preventing dry start of cam lobes.

My engine clearly has an obvious chain issue. Whether skip or stretch a replacement will solve it like it has for others. Sort of boring at this point with the exception if "skip back" actually works, it could be a solution for DIYers with a couple hours to spare. Anybody that has swapped or replaced a OCV could pop passenger valve cover off only, check alignment and skip back in a couple hours easy labor. But I am ahead of myself. I should know this weekend.

Until then am considering making a tool that will slide into position and allow easy skip back of timing chain. For those seeing nearly 10 degrees off at the crank. My self being the first to try. And if it works I will charge a fully refundable deposit for its use and return to all wish to give it a shot. Or post my design for others to copy or improve. First, I've got to see if I'm successful. I'm very hopefully despite wanting to start the V8 swap.

 

[FJtest]

Zunami -

The only question I have about your "skipped tooth/chain stretch" hypothesis is that you are using the external timing marks on the crank vibration damper as your crank timing reference mark, rather than the internal timing marks on the crank sprocket. Being a bonded-rubber damper, there is always a very slight chance that the external timing mark might not correspond with the internal timing mark if there has been any "slippage" in the damper because of rubber bond failure.

However, I am not aware of any reports of separation problems with the 1GR-FE damper.

I do have a cam chain removed from an engine that exhibited the P0016 DTC, and the DTC was corrected when the chain was replaced. (I don't recall if the VVT actuators were also replaced.) I haven't had a chance yet to measure link-to-link "clearance", and after measurement I will separate the chain at several locations to measure pin and bushing wear, look for galling, etc.

A quick look at the chain after solvent-cleaning to remove all oil didn't seem to indicate a chain with excessive pin-bushing clearance.

 

[FJtest]

Zunami -

One more thought .... you mentioned that "With the chain slack you can rotate the cams counterclockwise. The lock pins can be felt and heard "camming out" of locked position."

I don't think the lock pins should be capable of being "cammed out" of their locked position. They are supposed to remain in the "locked" position until they are released by oil pressure within the adjuster. If they can be mechanically cammed out of the locked position by applying torque to the camshaft or adjuster, something is not right.

How much torque needs to be applied to get them to disengage?

 

[ZUNAMI1]

I was able to move the chain this weekend and I NO longer have a P0016 ! It has worked so far after idling for 15 min while I cleaned up and for 12 miles driven only when the oil light came back on with blinking at first then steady.

Dropped the pan and had fresh "coffee grounds" sludge. Easy clean up this time but I had used sealer on the pan to reinstall which I won't do again until sludge is gone. I suspect the sludge is from my digging around the top end and not from clean action of additives.

I show in the pictures below how much sludge is drained (very little) and how much is left in the pan. Two table spoons. Enough to clog oil pick up screen. The oil is 75 miles old with sea foam and ATF in 4 quarts of 5-30w sacrificial, conventional oil. Pulled plug after driving a few miles, while engine warm. Oil warning light came one with no other noise or lights.

 

[Rust86]

Resurrection is real! Congrats!

 

[FJtest]

Zunami -

When you say "I was able to move the chain this weekend", do you mean you advanced the cam timing on both cam sprockets by 1 tooth?

It's kind of shocking that the added material thickness on the inner surface of the pan at the drain plug is so effective at blocking removal of the "coffee grounds".

 

[ZUNAMI1]

Zunami -

One more thought .... you mentioned that "With the chain slack you can rotate the cams counterclockwise. The lock pins can be felt and heard "camming out" of locked position."

I don't think the lock pins should be capable of being "cammed out" of their locked position. They are supposed to remain in the "locked" position until they are released by oil pressure within the adjuster. If they can be mechanically cammed out of the locked position by applying torque to the camshaft or adjuster, something is not right.

How much torque needs to be applied to get them to disengage?

First. No more p0016. Which is cool. Runs the same. Idled fast for a bit during warm up.

I will have the covers off again shortly and will pay particular attention to adjuster in relationship to the cam rotation. This was a secondary observation. What I believed I was able to see was adjuster movement without corresponding cam movement. But you may be right. There is alot of pressure coming from Valve Springs and it is a struggle to manipulate the chain with one hand while trying to steady the adjuster nut with wrench in the other.

As I stated, I was able to fix the p0016 error. My attempt to simply rotate the crank was circumvented by the bank one cam skipping through the chain several links due to pressure to cam lobes. At TDC bank one is spring loaded and as I was trying to get appropriate slack on the crank, it spun violently about 20 degrees. This is when I was mindful of lock poistion.

So I was stuck adjusting the chain the hard way at the adjuster which was successful so far. Error always came back within a minute or two previously. Haven't driven it since fluid change.

The video link below show an adjuster with cam lock pin "camming out" with rock back and forth.

At 6 minute mark, Producer of the video says its locked dead but clearly, as the video goes on, with spring removed he rocks it back and forth gently and it works it way back out. Zero torque. I was at 30lbs as a guess. I had a wrench on each adjuster and ratchet on crank.

My concern was in my adjustment of the chain I wanted to make sure I didn't set timing with pins unlocked. I believed I experienced an unlocked position while I was wrench with quit some force back and forth. I remember thinking I was unlocked.

I have to admit, I thought I cammed out the lock pin, but I am not positive. The cam wanted to be on either side of the lobes at TDC and I couldn't manage it by wrenching to position and dropping the chain on. So I was back and forth on each side of the high spot of the cam until gave up. I then dropped the chain on the gear and did an inch worm technique moving the slack chain on link at a time while keeping the rest in position using tension from bank two to keep the cam from spinning forward or back.

Check that video and let me know what you think. I will definitely try cam out again if I have to adjust again but right now I am fixed. No errors, no smoke, no bad sounds.

 

[ZUNAMI1]

Preliminary results are successful. No error codes. No lights but my test drive, which was Gorilla in nature, was shortened by sludge related oil light. but 20 minutes idle total and 15 miles or less test is good so far.
Lights were always quick to come on after battery disconnect.

Back together and working perfect.

 

[ZUNAMI1]

Resurrection is real! Congrats!

We'll see after some driving. I have no plates for this rig and several warnings from the Highway Patrol for failure to register within 3 days. So I am waiting for my plates to come by mail to put some serious miles on it. My drivers side OCV came in today, too late dang it, so I may remove covers to see how much alignment issue I have after a few miles.

Even this small hole was clear of sludge and not clogged.

 

[ZUNAMI1]

Zunami -

When you say "I was able to move the chain this weekend", do you mean you advanced the cam timing on both cam sprockets by 1 tooth?

It's kind of shocking that the added material thickness on the inner surface of the pan at the drain plug is so effective at blocking removal of the "coffee grounds".

Yes. One tooth advance on the cam adjuster sprocket. Quit easy to do retrospectively. The crank advance was not cooperating. I had the chain slip off bank 1 cam gear which predicated adjustment at cam gears rather than crank.

I would recommend adjusting at cam gears. The adjustment at the crank seems more intuitive but you are visually impaired while the cam gears are easy to see. I couldn't feel or hear the chain move on the crank and quickly lost orientation of crank in relation to the chain. With the tensioner off I is hard to tell where the crank is. Lots of slack and free rotation but no change in my attempt.

As far as the sludge goes: The sludge in the pan does not drain and what remains due to the raised profile within the pan by the bung or threaded "nut" holds the sludge in. I used ramps to get under my rig. If you wanted to drain the type of sludge I experienced you could effectively place a ramp under drivers side only thereby tilting the car / pan towards drain hole and it would remove more. Enough, anyway, to prevent the clogging effect.

I took a video:

https://youtu.be/YmT8vHmaCbQ

I got the red oil light with this amount. The pictures previous posted with 190 micron filter show just how little drained and how much remained in the pan. Simply changing the oil and I would have drawn an oil light again with all certainty.