Help me Diagnose Knocking Sound

abs

New member
My Ford Flex has a remanufactured Ford 3.5L ecoboost engine in it with about 40k miles on it.  The original engine failed horribly at about 105k due to a water pump seal failure dumping coolant into the original engine.  This new/reman engine is making a knocking noise and I can't figure out what it is.  I do not know if the reman engine has the upgraded timing chain or not, it was installed in 2014.

I just posted a video to YouTube, please watch it and let me know if you can identify what the sound is:

https://youtu.be/WUqRevmQ1hc

The engine is running pretty good, pulls hard under full throttle.  It is not leaking coolant that I can see and the degas bottle shows full, I haven't needed to top it off or refill it.  The sound is coming from the front of the engine, it seems to be coming from the middle/top of the timing chain cover.  I have new plugs in it and the engine is not misfiring (checked with Mode 6 in Forscan).  I've also run fuel injector cleaner for a few tanks of gas and I do not believe I have a fuel issue.  My fuel rail pressures meet factory spec.  When I listen to the sound of each of the camshaft phasers by putting my ear to a long screwdriver, the front phaser sounds different than the rear one, but neither one sounds like its knocking.  I've also heard the sound of failed cam phasers in other YouTube videos, this sound is different.

I'm thinking the sound could be from a worn water pump bearing allowing the pump impeller to hit the engine block.  It could also be the timing chain itself knocking around due to a damaged tensioner, guide or chain stretch.  It could also be a piston wrist pin or connecting rod.  If anyone can confirm what this sound is would be greatly appreciated. 

Thanks!
 
Sounds like lifters, too. Have you tried Lucas oil stabilizer?  If not, add some and see if it makes difference.
 
Yeah, a heavier weight oil might help.  Are you running 5W20 or 5W30 currently?  5W30 is recommended unless the remanned engine specifically said to use 5W20.  I would try 5W30 anyway LOL.

I would suspect timing components myself, maybe slack in the chains/tensioner involvement.  If you track via PIDs, see if there are VCT related PIDs, check them while the engine is idling like in the video.  A certain degree of error is tolerable, but usually should be near zero at idle.  If there is rattle at startup, that would add weight to the timing hypothesis.
 
Thanks all for the replies.  I've been running 5w-30 full synthetic oils since the reman engine went in.  I do use Forscan and I've noticed a minor error in the camshaft timing, but I don't recall the % error off-hand.  I'll check that and post back here. 

It is hard to determine the source of that sound, but to me, it really does seem like it is coming from the area of the timing cover where the water pump is located, just below the engine mount.  I have seen videos where the plastic vanes on the water pump were damaged, broken and sheared off, from the pump bearing failing and the vanes knocking into the block.  I wonder if that is what could be happening here?

The EB has solid bucket style valve actuators, I'm not really sure how this noise could be caused by them unless a valve lash is really out of adjustment and needs a new bucket actuator to tighten it up, but with only 40k miles, I wonder if that is a realistic possibility?

I do not suffer from any meaningful startup rattle - I know that sound from my original engine and also from many videos.  At this moment, my engine does not suffer from it . . . However, that does not mean there couldn't be some other problem with the timing system.

Please keep the ideas coming as I have to decide my next step for diagnosing what is happening.  I'm not looking forward to pulling the timing chain cover, but I'll do that if I have to.
 
While we wait for responses, I was thinking of possibly bringing this up with Ford/Ford Engineering directly.  This IS a ford remanned engine right?  They may be able to help you technically, if not financially.

A new water pump should have been installed with a remanned engine.  Yes, the vanes can break, not at all frequent, but it can happen.
 
2 suggestions.

First:

A pulley is knocking. What is the main belt like? etc.

Second:

Phaser(s) failed. Maybe causing the belt to slacken.

Different motors but maybe useful videos.

https://youtu.be/OFhvUFtnBCk

https://youtu.be/iEBic0fEZ78

Watch them and see what you think.
 
All -

Thank you for the feedback, it's been a crazy work week, and I haven't had a chance to get back to do additional testing yet.  However, the engine is out of warranty as it was installed in 2014 so past the warranty time limit. 

In terms of next steps, I will take off the belt to see if the noise is from the belt tensioner, alternator or a/c compressor.  I suppose if I pull the valve covers I could check the lifter gaps and see if maybe that is the issue.  This engine does not have hydraulic lifters so the entire valve train setup is fairly straightforward.  I also do have the ability to monitor knock, and I've looked at briefly in the past but didn't notice anything unusual with timing retard.  It also occurred to me that I should inspect the rear turbo for noise.  I installed a used turbo there about 5k miles ago.

The one thing I am most worried about is if this could be due to a cracked piston skirt.  I was able to find some references/posts related to Youtube videos where that seemed to be the diagnosis for an engine with a similar noise.

I'll post more over the weekend.
 
I've carefully reviewed all of FordTechMakuloco's videos as well as other videos with failing cam phasers on Ford vehicles, and in every case I could find, the sound of the bad phaser was very consistent and repetitive.  The sound on my car is much more intermittent. 

Tonight I went out with the mechanic's stethoscope and poked around the top of the engine with it.  The knock sound is not detectable on or around any part of either valve cover.  It is also not detectable along the top of the block in between the valve cover and where the aluminum intake bolts down, except for at the timing chain side of the engine in the V near the engine mount, where the sound is noticeable on both heads.  It does not sound louder or quieter on either side.  Checking below the engine mount and getting closer to the water pump mount location, the sound intensity increases.  I can also hear the sound on the side of the rear head (firewall side) towards the bottom of that head.  I also checked the front exhaust manifold where it bolts to the head and there were no irregular noises.  I listened to the mounting bracket for the rear turbo and did not hear the noise which I think rules out the rear turbo.  Disconnecting the power to the variable camshaft actuators made no change.  I did notice that when I put my hand on the electrical connector for the front cam phaser actuator, that the there was a lot of pulsing/vibration, but the rear actuator did not have the same feeling.  Also, the noise is also still there at higher RPM's, but much harder to detect as other noises tend to swamp it out. 

At this point, I am leaning toward one of the following possibilities:

- Water Pump rattling and perhaps in early stages of failure
- Cam Phaser(s) or actuators
- Damage chain guides
- Damaged piston skirt on cylinder #1 or #4

Also, I remembered that for my last oil change, I used Mobil 1 Advanced Fuel Economy 0W-30 plus a quart of Mobil1 10w-30.  At operating temps, this oil should not be any thinner than the OEM spec 5W-20, but perhaps the oil has something to do with it.  I could easily do a quick oil change to a 10W-30 and see if it makes a difference.

I think my next step is to perform the oil change and also get under the car and make sure the noise is not louder at the oil pan or lower end of the engine.

Thoughts?
 
I think SHOdded was Spot on ^^^

Stick to what the oil cap says!
The engines MUST have the right weight-viscosity of engine oil. The PCM opens up valves to control the cam phasers based on the correct oil. Too heavy or too light and the cam phaser will over-react or under-react. The VCT phaser not responding correctly to the PCM! Z


 
ZSHO said:
I think SHOdded was Spot on ^^^

Stick to what the oil cap says!
The engines MUST have the right weight-viscosity of engine oil. The PCM opens up valves to control the cam phasers based on the correct oil. Too heavy or too light and the cam phaser will over-react or under-react. The VCT phaser not responding correctly to the PCM! Z

I am going to also agree.  Mixing oil on some cars doesn't seem to matter.  But for others it generates unexpected results.  My old mildy built g35 was the same way.  After dropping nismo cams and a head rebuild and a orsis tune the builder SWORE by 0-20/5-30 hybrid .. keep throwing p0340 on hard rapid accelerations in the summer.. switched back to 5-30 and it was fine. 


drop back to oem oil, drop the tune to stock drive normal for 500 miles and retest with the oem tune.

EDIT :: no additives, of any kind if you want extra metals for film strength go with royal purple oils.  just don't add any gunk. 
 
ZSHO and TOPHERSHO:

I appreciate your feedback but I started laughing reading both of your posts.  I would agree that there can be some differences in engine performance based on viscosity, primarily fuel economy as a function of HTHS.  However, I hope you both realize that even a 0W weight oil is much much much more viscous at cold temperatures than a 30, 40 or even 50 weight oil at operating temperature?  Also, do you realize that the difference in oil performance at operating temperature between a 20, 30 or 40 weight oil is very, very small?  Also, you know that oil can shear down and thin out over time as it's used and from oil dilution so much so that a 30 can become a 20 and so on?  All of this points to one thing:  The PCM is perfectly capable of adjusting the cam phaser performance for a variety of oil flow rates and viscosities.  Also, keep in mind that for the 2011 MY, Ford spec'd a 5w-30 oil even though nothing in the engine changed from 2010 to 2011 . . . I'm fairly certain that the oil is not actually the cause of the noise I've been experiencing, but I'm willing to do an oil change to see if it makes a difference.  Oh, one other thing, this engine is not tuned . . .
 
Well, best of luck, hopefully you can figure out what actually is the matter with the engine.  As for whether the engine changed internally or not, only an insider can tell us that for sure.  My feeling is better fuel dilution handling, but it could be something else as well.  Many changes do not make it to part number updates or to the catalogs.

Viscosities are a dubious area, but if you are willing to experiment, more power to you.  Whenever we ask for documented results of these types of things, such as a used oil analysis done consistently over a period of time, it has been crickets.  So if others' opinions holds no weight with you, that is OK.  But please, be courteous in your response.  You trust your experience, others trust theirs too!
 
abs said:
ZSHO and TOPHERSHO:

I appreciate your feedback but I started laughing reading both of your posts.  I would agree that there can be some differences in engine performance based on viscosity, primarily fuel economy as a function of HTHS.  However, I hope you both realize that even a 0W weight oil is much much much more viscous at cold temperatures than a 30, 40 or even 50 weight oil at operating temperature?  Also, do you realize that the difference in oil performance at operating temperature between a 20, 30 or 40 weight oil is very, very small?  Also, you know that oil can shear down and thin out over time as it's used and from oil dilution so much so that a 30 can become a 20 and so on?  All of this points to one thing:  The PCM is perfectly capable of adjusting the cam phaser performance for a variety of oil flow rates and viscosities.  Also, keep in mind that for the 2011 MY, Ford spec'd a 5w-30 oil even though nothing in the engine changed from 2010 to 2011 . . . I'm fairly certain that the oil is not actually the cause of the noise I've been experiencing, but I'm willing to do an oil change to see if it makes a difference.  Oh, one other thing, this engine is not tuned . . .
How many miles since your last oil change! FYI- Dirty oil alone,specifically oil that has depleted the anti-foam additives will cause a slight delay in the response of the cam phasers!!
Change the oil and see if your issues goes away and report back.

There's No need to get snarky and simply trying to help a fellow member out that's all! Z
 
All -

Apologies if my response came across the wrong way, I do appreciate everyone's input and I am thankful for the responses and the help.  I want to solve this issue and maybe help some other ecoboost owners in the process too!

For those interested in learning more about motor oil, the website forum at www.bobistheoilguy.com is really good.  There are UOAs available for ecoboost engines posted on the site as well as lots of discussion about the impact of different viscosities and other oil attributes.  I highly recommend the site and I have spent countless hours researching all kinds of fluids there.  I've also started ecoboost specific threads regarding oil options on that site in past. 

I did recently change the oil, just about 1500 miles ago, but I also ran a few rounds of fuel injector cleaner on multiple tanks of fuel which may have consumed some/much of the additives.  I'll change the oil and report back if there is any change.  To be honest, it would be great if this solves the problem since it's a very easy fix.
 
Fingers crossed :)  What fuel injector cleaner did you use, and was it used in consecutive tanks? 

As a general rule, if you use a stronger cleaner such as Techron Concentrate Plus or BG 44K or Redline etc., even though they do not state to change the oil after, my advice is to err on the side of caution.  Change the oil after that tank is done.  Why?  Dealing with unknowns.  We never have any idea how much cushion we have after a servicing is done.  And to me, changing oil/filter is a no-brainer way after each cleaning to avoid complications.

I have found benefit from adding TC-W3 oil or Lucas UCL/FIC to the tank for every run in wintertime.  Some use MMO.  In the small quantities stated (4.5-5oz per tank), they will do no harm.  The benefit is cleaning AND lubrication for the injectors, especially good if you run E blend fuels.

BTW, there are a few stalwarts on BITOG (DuckRyder, Subie, etc) that know what they are talking about, but really very few yet that understand boosted/Ecoboost engines.  The sheer misinformed (though wellmeaning) analysis of fuel in the oil blows my mind.  And yet many others that do not understand the engine breakin process does NOT have the same effect on every engine line across all the manufacturers in the world.
 
Since my last oil change I ran a tank of LiquiMoly Jektron cleaner and a second tank with Redline Fuel System cleaner, they were not run back to back but with only one normal tank in-between.  I agree that these cleaners could have had an effect on the oil and might be part of what is happening.

There are some other very knowledgeable folks on that BITOG board including Molekule and Chatterham.  Having said that, the quality of some of the content on that board has declined as more people have begun to participate.  I've been an active member there for many years and I've noted the changes . . . It is important to discern what is real versus hyperbole and what is fact based versus assumption at this point.

For a period of time I was regularly running Lucas UCL or MMO in my Flex, but eventually I stopped.  I've never tried the TC-W3 although I've read good things.  By the way some very interesting tests of combustion chamber cleaners which you might enjoy watching here:

https://www.youtube.com/watch?v=BPdz6BMj8EA
https://www.youtube.com/watch?v=vVyin2n24X8
https://www.youtube.com/watch?v=tX-h62PUu0o
https://www.youtube.com/watch?v=IOCvfQD8Tqk
 
Yes, I am familiar with Project Farm, have watched a LOT of his videos. also watched Chris Fix, fordTechMakuloco, Scotty Kilmer, south main auto, there is no shortage of consumption on my part LOL.  Also spent plenty of time talking to formulators at oil companies, ultimately they are obliged not to say anything pertinent or I am bound not to.  I read technical papers published by reaserchers, independent or otherwise.  I can name many other knowledgeable people at BITOG as well, but I dont.  The problem is, none of this is really first hand knowledge.  But the cleaners I have mentioned, I DO have 1st hand experience with, so that is what I talk about. 

Anyhoo, sorry for rambling on.  Lets see if we can get the issues with your ride resolved :)
 
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