NEED HELP Bad knocking

[redline customs]

Alright guys mY 03 is having a bad knocking sound. I pulled code p0014(exhaust camshaft timing over advanced). Since I have had a code for my camshaft actuator solenoid I replaced that as well as a fresh oil change. Still have the noise but it goes in and out. I'm still getting the same code. The next day after the change(which I did the day before yesterday) I started it up in the morning and the thing sounds like it has a cam. I have 2 or 3 dead cylinders at idle until it warms up and 1 dead cylinder all the time. I'm not getting any codes for a misfire. Anyone know what it could be? At first I was thinking maybe the piston was hitting valves but I was told this is a non interference engine. Anyone verify this? Could this be a timing chain that stretched horribly? There was no warning, no slow tick that lead up to this(it did have a tick but I'm pretty sure its the fan clutch). It just started all of a sudden a couple weeks ago then just completely went away after about 10 mins. Started up again and has t gone away.
Here is a link to a video of the noise.

 

[Mooseman]

Two things come to mind. A bad valve lifter or the cam phaser is bad, which could be the reason for the p0014.

Does the noise get worse with RPM increase?

 

[redline customs]

Not really worse but it does "follow" the rpms. I.e. higher rpm the noise gets faster

 

[Sparky]

The first code makes me think the phaser went out on you, perhaps.

 

[redline customs]

Would that make the knocking noise? It definitely seems to be valve timing related considering the idle miss. Would you think it could be the timing chain tensioner gone bad or a guide?

 

[Sparky]

Could be. I recall seeing a video of a bad phaser that had a lot of slop and rattled internally. Hard to say until you take the cover off and look (which would let you check the chain and all that too).

 

[redline customs]

Any write ups on taking the cover off?

 

[Capote]

Any write ups on taking the cover off?

There should be some on here, there's also some YouTube videos as well. Valve cover is relatively simple to take off. Remove intake, throttle body, pcm, intake minofold, fuel rail, coil packs, and then its pretty much all the surrounding bolts on the exterior of the valve cover. You also will need to remove the timing chain gaurd. You'll need to keep tension on the timing chain with bungee cords or wire so it doesnt slip off the cam phaser and etc. There's plenty of ways to go about that.

 

[redline customs]

OK once I get it off, is there anyway to test the phaser or is it visual inspection only? Tried using search but it just brings up a bunch of random crap. Any thread that has timing or cover mentioned in it pops up

 

[Capote]

Im not aware of any troubleshooting to test the cam phaser at that point, I'm sure the rest can chime in on that.

 

[Sparky]

It shouldn't wobble back and forth. If it is sloppy/loose at all then it has self destructed.

 

[mrrsm]

I'm yielding to everybody's idea of investigating the Cam Phaser Solenoid First... in part because it also makes sense to swap it out if the vehicle is one with very high mileage and its also a fairly in-expensive and easy R&R...

...But Boy after listening to so many of these Audio-Videos of people having Suspicious Engine Noises lately... that it sounds very much like something involving the Flex-Plate or perhaps the WATER PUMP BEARINGS HAVE FAILED... Listen to this... noting that the noise sounds rhythmically very much like yours and is primarily closer to the front of the engine.

@redline customs DON'T PULL THE VALVE COVER OFF JUST YET... If you take off your Serpentine Belt and Start the Engine and run it very briefly...If the Engine Knock subsides... then the WP is probably the Bad Guy in The Story:

If the WP turns out to be the Culprit... This Video Shows How to Do The Job:

I'm not aware of any troubleshooting to test the cam phaser at that point, I'm sure the rest can chime in on that.

This Fellow seems to have a Good Video on what to do on this:

This is probably the Simplest Generic Method to use when Testing whether or not the VVT CPAS Unit is working "ON or OFF" under a Basic Closed-Open Solenoid Circuit Test. This is being done when it is NOT installed in the Engine Head and NOT part of the PCM Circuit or being evaluated dynamically when the engine is running in concert with a more sophisticated Scanner Diagnostic Tool:

 

[webdawg]

If you take off your Serpentine Belt and Start the Engine and run it very briefly...If the Engine Knock subsides... then the WP is probably the Bad Guy in The Story

Why did I not think about doing this...This should not hurt anything right, will I have codes to clear after that?

 

[mrrsm]

No Brother... Don't worry about the codes...What is happening to make all the racket is that the "Hollow" that the WP sits inside of is picking up the "Chug-Chug" of the Sketchy Bad Bearings/Races that are off -kilter...and the Hollow Area Front of the "BOX" shape of the Atlas Engine and Lower Crankcase acts like a Kettle Drum being Tapped with a Soup Spoon.

A Small Bearing Vibration Input like this in there is Greatly Amplified... and it causes that inordinately loud "Rod-Knocking End of the World" Sound as a result. If the sound your own engine was making cannot be heard after you pull the Serpentine Belt and Start and idle the Engine (very briefly...or a weak battery won't start the engine if it is run too long)... then The Water Pump needs an R&R ASAP using ONLY an OEM New AC-Delco flavour... as After-Market WPs simply... will NOT do!

(see @dvasnicka 's Epic Post on the WP Repair)

Watch How @MAY03LT does this very same manoeuvre to Diagnose a Bad High-Performance After-Market Alternator... A Different Component... But SO MANY OF THE BELT DRIVEN COMPONENTS WILL REVEAL THEMSELVES...SIMPLY BY TEMPORARILY PULLING THE SERPENTINE BELT...THEN STARTING THE ENGINE....AND LISTENING TO THE SILENCE THAT FOLLOWS! ;>)

 

[Mooseman]

The knocking is too regular to be the chain tensioner.

Cam phaser itself can only be tested with a Tech 2 after confirming that's it's not the CPAS solenoid after replacing with a new one.

But before all that, that knocking is worrying to me. Too regular in my ears to be the water pump but definitely a good idea to take off the belt to eliminate anything belt driven. After the belt test, if the noise is still there, I'd remove the valve cover and investigate the valvetrain, especially if it sounds like it's coming from on top or can feel it on the valve cover. There have been others that had valve lifters and rockers fail.
Remove the intake manifold and valve cover

 

[mrrsm]

--^-- X2... Hopefully... THIS is not what is under there...

 

[djthumper]

OK once I get it off, is there anyway to test the phaser or is it visual inspection only? Tried using search but it just brings up a bunch of random crap. Any thread that has timing or cover mentioned in it pops up

The sites search is not that great. When using google you can put in your search term followed by "site:gmtnation.com" will search GMTN and give you any results we have.

 

[redline customs]

Thanks guys, I failed to mention that I did run without the belt yesterday. Wanted to make sure it was not the fan clutch ticking getting worse so all that's out because it kept it right up. I replaced the solenoid(mine had oil in it) as well as blew out and cleaned the plug. I didn't bother checking the old one because the screens were clogged. After the replacement, the noise seems to go away for a minute then come back. Also the noise gets very loud if I accelerate then let off. Both of these are kind of what led me to believe something with the timing chain. When it is cold I will have 2-3 dead cylinders and it sounds like a cammed v8 with all the loping(actually had a guy ask me of I had a can a bit ago). After it warms up, the lopeyness goes away but I still have one dead cylinder. This cylinder is dead throughout the rpm range and the noise seems to be connected to this cylinder but that may just be hearing lag. I am not getting any codes other than for the p0014. Seems like I should have a misfire code, but I digress. I changed the oil while I was replacing the solenoid and while it was due for a change, there were no sparkles or grittiness to it. I do my best to change every 2800- 3k but I just reached the 3500 mark on this one due to working a ton of hours. I tried to feel of the valve cover to see if I could feel the tap at anyone spot, but the engine was vibrating too badly. I seen something about plugging the hole from the crankcase to the intake and seeing if it takes the noise away or quiets it, but the only noteable occurance was a shit ton of vacuum on my finger. After removing my finger it was actually whistling while sucking in air(not sure if its supposed to do that or not). I'm not a novice by any means, I can find my way around an engine, but this has got me(and I know once I find it, it will be embarrassingly stupid). I do appreciate all of yalls help and suggestions. Oh and the tb just rolled over 171k if that helps(probably not much). I am unaware of the service that has been done before I got it, but seems to be pretty well maintained.

 

[Mooseman]

If the engine had a dead cylinder, you would get a P030x code with x being the missing cylinder. If it doesn't know which, it would give P0300.

Maybe another thing you could do is a compression test on all the cylinders. If one is noticeably different, it could give us a clue.

One possibility, and I'm going out on a limb here, is that the cam phaser is stuck in the fully advanced position and making the engine so rough it's like a missing cylinder. While playing with the Tech 2, I advanced the cam phaser manually and the engine would run really rough. But that would still not account for the ticking/knocking noise.

 

[redline customs]

I'm only saying dead as I guess a metaphor. The miss is so bad it sounds dead lol. Also I get horrible exhaust smell when its warming up and has a couple of "dead" cylinders. I'm guessing that means its not firing the fuel? The fact that it comes back to life so to speak after it warms up has me baffled.

 

[mrrsm]

A Complete Oil and Filter change is necessary when doing the CPAS R&R because the New One will rapidly clog without one. An Oil Filter Autopsy with Kerosene Wash in Plastic Bucket is in order, too...with a thorough sweep of the Washings using a Neodymium Magnet... as well as a visual search for any light weight Non-Ferrous Metal Particles nested in the Filter Folds. This might reveal anything physical breaking down and dropping into the Crankcase-Oilpan.

Pulling and "Reading" the Spark Plugs and looking for a consistent "Fried Chicken Brown" appearance would help to pin down the cylinders you already suspect... If they are coated with Gas and Oil... It's a sure sign of a loss of compression due to leaking valves or rings... or one or more Failed Coil On Plug Units. If you decide to do this... if you will post the images of how the plugs look here in sequence 1-6... It will be valued in the future by other Members looking into their own similar issues and in need of diagnostic guidance.

 

[m.mcmillen]

The knocking is too regular to be the chain tensioner.

Cam phaser itself can only be tested with a Tech 2 after confirming that's it's not the CPAS solenoid after replacing with a new one.

You don't have to have a Tech 2 to test the phaser. My Snap On scanner can do the test. If you can find a good local shop that has a Snap On scanner, they would test it for you and save a trip to the dealer$ship.



I recently changed all of my lash adjusters. I removed the PCM, intake manifold, all of the coils, and the valve cover. The fuel rail does not need to come out. All you need to do is disconnect the two fuel lines. If I remember correctly, the alternator had to come off also to access one of the bolts for the intake manifold. Let me know if you have any questions.

 

[redline customs]

Yep did the filter too. I will see what the old one looks like. I would be happy to pull the plugs and post pics(could probably use new plugs anyway) but it may be a couple days before I can get to it

 

[mrrsm]

FWIW… Another “Sound and Fury” Video to compare with the OP’s:

This kid “Octane” shot a “Super Close-Up” right down the tube of the Oil Filler Neck in the Valve Cover that has a similar knocking sound in his engine as the OP’s. But when I first looked/listened to the video… since he never mentions anything about WTF it was that he was working on, I was not even sure whether or not this was a GM Atlas 4.2L Engine to begin with. Also, I've never seen any of the Vortec Late Model Metal Valve Covers that are either Anodized or Powder Coated in BLACK… so I glommed this video anyway... and kept poking around to see if he had other videos to clarify the question:

Sure enough… a while later… he made THIS video that confirms that the motor is indeed a GM 4.2L Engine. But he makes an inconclusive attempt to explain what HIS impression of what the actual underlying mechanical problems were; which only prompted the comments posters to ask more questions. This is a 'A Cautionary Tale' about what can go wrong in such cases when work like this is being done by those without any experience or guidance… and what ultimately will have to be done to repair the problem via a Professional Mechanic:

 

[mrrsm]

You don't have to have a Tech 2 to test the phaser. My Snap On scanner can do the test. If you can find a good local shop that has a Snap On scanner, they would test it for you and save a trip to the dealer$ship.

View attachment 78537

I recently changed all of my lash adjusters. I removed the PCM, intake manifold, all of the coils, and the valve cover. The fuel rail does not need to come out. All you need to do is disconnect the two fuel lines. If I remember correctly, the alternator had to come off also to access one of the bolts for the intake manifold. Let me know if you have any questions.
View attachment 78537

A small HJk...
Would you mention where you got your OEM Valve Lash Adjusters? I just had two come in via eBay without any original GM or AC-Delco OEM Plastic Bags and they look suspiciously low quality...and "Cheesy-Chinese"... Thanks.

 

[m.mcmillen]

I bought them from the dealer. As much work as it was to change them, I didn't want to risk it with an aftermarket. The part number is 12572638.

 

[Mooseman]

If I remember correctly, the alternator had to come off also to access one of the bolts for the intake manifold.

I never had to remove the alternator. Removing the bottom bolt for the bracket that holds the fuel lines and wiring harnesses is a PITA though.

@MRRSM , that would be our former (or should I say inactive) member OctaneRider. He had replaced the head on his truck and eventually did work until some lifters failed a couple of months after that video. Here's the whole 13 pages of his adventure:
http://gmtnation.com/forums/threads/4-2l-i6-head-removal-engine-restoration.4373/

The noise sure sounds similar as that first video with the timing chain that was off by a tooth after replacing the head. In the OP's case, the engine hasn't been opened yet. I had a failed chain tensioner and drove it for a while until I could fix it but the chain never skipped a tooth so I can't see how the chain would be off.

 

[mrrsm]

Well My Goodness... He seems very young... and watching him Rev the Engine unloaded to 7,000 RPM after FUBARing the First Motor... and then and him losing 3rd Gear in the Transmission during the repair...Whew... This Marine...If he were my son... I'd have to keep an eye on him...:>)

Thanks for the additional "Read" on his situation... I never get over How Much New Stuff I get to learn... from YOU! I LIKE it!

UPDATE:

I remember this Fellow now... Yeah...
OMG....
ROFLOL
I'm Sorry, Dude...
430 Posts...& -----"0"------- Likes...?

OMG-->This Poor Kid... Jesus Palomino... Some People Could FU a Soup Sandwich!
https://www.youtube.com/user/EricTheCarGuy
And THIS Sez It ALL...

EricTheCarGuy4 years ago
"My guess would be over revving or that the parts were not installed correctly. It's strange because everything looks so new inside there. P.S. get used to difficult dis-assemblies. I'm sure it won't be the first time. Good luck in school."

 

[mrrsm]

Since the video mentioned above might be useful on the OP's Engine Knock issues... Here are ALL of OctaneRider03’s correlated Qik Videos converted and properly loaded up to Youtube but since they are NOT Numbered...their sequence might be a bit out of order:

You just cannot watch these videos and NOT feel sorry for this Young Marine.
@MAY03LT would probably say…“Damn Dude... You Know What I’m Saying, Man…?”

This Topic should be called “The GM Atlas 4.2L Engine Repair TRAIN WRECK”:

Notice the Problem with the Exhaust Camshaft Phaser? The word “DELPHI” is canted clockwise and NOT Horizontal and will NOT be Level with the upper edge of the Aluminum Head if installed in this position:

...which may explain why THIS happened a little later:

In this RARE event...This is his visit to a Machine Shop Video discussing this Head Repair:
https://www.youtube.com/watch?v=CXGqVUs558Y

 

[Mooseman]

He has 0 likes because that was before the likes system existed.

We were following his work, sometimes live when he was streaming on Qik, and our hearts just sank when it happened. Nothing came easy for him.

I saw in that video that he revved it to 7k but have a feeling that for 3 or more of those to fail at the same time could have been caused by some sort of abuse. In all fairness to the departed, he didn't tell us how it died so we can only speculate. It could have also been a problem with the rebuilt head.

 

[mrrsm]

Well it is a HUGE CRYING SHAME to watch him walk around his Truck.. with such a sense of affection and pride as he tells us all about it...and yet to be troubled with an ingrained natural ability to unintentionally destroy so many mechanical things. I suspect that since his vehicle had NO PLASTIC SHROUD INSTALLED and with that Fan going "10-8" constantly... it was inevitable that the eventually the engine would overheat...and since he mentioned needing to get a New Radiator.... Installing a brand new shroud probably seemed like a waste of money... or perhaps his "helper" was just too burned out in the end to bother putting the old, damaged one back in.

In any case... Because he was brave enough to go 12,000 Miles away to the ass-end of The World, time and again to serve his country and put himself in Harm's Way for the USA... its a God-damned shame he did not have a good local group of experienced GMT-360 Folks at each of his Military Bases he was assigned at...to sort of take him under their wing. What The Oracle in "The Matrix" told Neo in her Kitchen seems very appropriate to mention here in the context of his strange sort of innocence ...and good character:

"You have a Good Soul... Neo ... And I HATE Giving Good People...BAD NEWS..."

 

[Mooseman]

I think we need to bring this back to topic.(Yes, I'm just as guilty for the )

We need to hear back from the OP.

 

[redline customs]

Thanks guys lol. Had to read a couple times over to figure out what was going on( internet is super slow so the videos never appeared till I thought you all were crazy talking about them). I will(hopefully) be able to get the valve cover off on Sunday(if I actually get off) and will post pics. I'm scared as to what I will find but I figure it needs to be done.
@Mooseman, do you think if could be possible for it to skip a tooth? I know you said it did not in your case but could it be possible? Its just odd to me that(not sure if I mentioned it or not) the noise will be louder after a slight accellaration and letting off. It will be loud right as I let off then go away for a bit(that seems to be the only constant,otherwise its more or less random as for appearance and volume). Also weird that I will have 2-3 cylinders misfiring at idle, then when warmed up(or above idle) it only seems to have one cylinder misfiring. Any thoughts on that?

 

[Mooseman]

Anything is possible. Hopefully it is one of the cam gears it skipped and not the crank gear which I have no idea how to check without taking the chain cover off, which would require the removal of the oil pan.

 

[mrrsm]

Strangely enough... All Three Sprockets have such very shallow teeth concavities that they don't look like they could ever hang on to the chain very well. There is also the long distance the Timing Chain Tensioner Plunger can travel if it were to collapse inward and add a lot of extra slack. If the Light Green Nylon Foot Pad on the Timing Chain Tensioner Plunger ages enough from the heat and chemicals, it turns brown and flaky enough to crack and fall apart after being squashed against the outside of passenger Timing Chain Chain Guide.

It would not surprise me if enough slack on the clockwise upswing "slack chain" side might be be possible when the chain is on the rise towards the passive Cam Phaser. If after pulling under very hard acceleration, a sudden deceleration could cause the chain to whip towards the Crankshaft Cog as it relaxes. With enough slack right there... it might become just loose enough for it to skip a tooth or two. Does your model of this Atlas Engine have also have the Top Overhead Chain Guide to resist this action from happening?

This video gives a Bird's Eye View of how much room there is down at the bottom of the block where a whipping chain might pass a tooth under just the "Right Wrong" conditions. The only other question that remains ais "The Pachyderm in the Room" is:

"Did the Prior Owner ever Remove and Re-install the Timing Chain Set Before?"

 

[redline customs]

i have no idea about what the previous owner did. I'm not accelerating very hard for it to do it. I've been trying to be extra babyish with it to avoid further damage. If I had another vehicle then I would park this until its fixed, but at this point that is unfortunately the case

 

[redline customs]

Well I was coming home from work and lost almost all power. Had to downshift to make it up a very small hill. At the same time, it went from sounding like one marble in the engine to about 50. It honestly sounds like the timing chain is catching on something and ea ch link is making a sound. It may be something broke off and is bouncing around.

 

[Mooseman]

Could very well be. Someone did have the chain tensioner shoe fall off.

 

[redline customs]

Well... She finally kicked bricks. Started up a small hill yesterday, she bogged down real bad then I heard a pop and she never made it up the hill. Rolled it into a parking lot until me and my buddy went to get er last night. When I got there, there was a small puddle of(I'm assuming) oil under the tail pipe. Never had that before but idk. She turn over just fine and tries to fire once or twice so I'm assuming the chain snapped or fell off or something. I started the teardown t his morning.

 

[redline customs]

Update. Sorry that apparently wasn't oil. My mom picked us up when she died and my daughter spilt her water on the tailpipe out her door(side dumped) and it was the carbon mixing with water.