CX-5 Tapping noise

[Jack Rabbit]

Ok. Engine has been making noise for some time now. Indy mechanic last year said its just injectors. Took to dealer last year to have whole car checked out and said check the engine for any problems, especially cracked cylinder head. Vocally mentioned the sound and was told it's the injectors. They had the vehicle and heard it running.

I usually jump in my car and startup and then drive.

So today, while checking the brakes, left vehicle idling to go get my wheelchocks, and heard this from 60 feet away.

Sure sounds like the valves to me.

Also if you listen you can hear both the injectors clicking but you can also hear the tapping noise.

And it hasn't thrown any engine related codes.

Any opinions?
Lifters, HLA's or injectors ???
Thanks.

 

[macker]

That's a good plan, and should result in a decent chance that they'll be able to confirm the excessive noise, and move forward to diagnose further. Have you had any discussion with your dealer about the 'air bubble' TSB? If not you might want to bring up the subject when you drop it off, because that's the only document that I'm aware of which gives them the go ahead to pull the valve cover to test the switchable HLAs, and get warranty reimbursement from Mazda for their work.



The warm up routine that you posted above is another very helpful piece of information. I've always wondered about a possible relationship of engine noise and issues, to very short warm ups (or none at all). Although a sample size of one certainly is not proof of anything (either way), nevertheless it does show there's at least one case of this noise happening on a vehicle that's always given more than enough time to warm up.

And the typical driving pattern that you mentioned completes the trifecta which indicates a very well maintained and operated vehicle. So now I'm even more interested in what happens with your vehicle going forward, and @Jack Rabbit's as well. And a big shout out to you for taking the time to share all of this information, which may very well turn out to be important in trying to understand the scope and impact of the root cause of the noise

I've discussed/referenced the service alert on the HLA's and the service advisor acknowledged it. I also sent the service advisor my video clip and she shared it with one of their Techs and agreed this is not normal and *may* be related to the Mazda Service Alert mentioned.

I've owned a lot of cars over the years, and my start up habits of warming them up haven't changed and never had one that displays the noisy behavior of the CX-5 in cold weather. I started the car up this morning (late) and the temp was about +6 C and the engine sounded normal, though if I put my head next to the front grill I can hear a much more muted level of tapping. I let the car run for about 5 mins. with no change.

Glad to be part of this owners forum to share info. and hopefully we can all benefit from it in one way or another.

 

[macker]

Don't know the maintenance record of prior owner, but bought as CPO and oil changes between 5000 and 7500 miles.

In winter, car is warmed up for 5 to 10 minutes to defrost windshield before driving.

The tapping was not on engine start but occured at idle after the car had been idling for over a few minutes.

I also purchased mine used from a Mazda dealer, with just over 19,000 kms. on it. The owner (I believe a Dr.), had leased it and turned it back into the dealer. All service was done by the dealer and they shared the records with me. No red flags.

 

[yrwei52]

Ok. Engine has been making noise for some time now. Indy mechanic last year said its just injectors. Took to dealer last year to have whole car checked out and said check the engine for any problems, especially cracked cylinder head. Vocally mentioned the sound and was told it's the injectors. They had the vehicle and heard it running.

I usually jump in my car and startup and then drive.

So today, while checking the brakes, left vehicle idling to go get my wheelchocks, and heard this from 60 feet away.

Sure sounds like the valves to me.

Also if you listen you can hear both the injectors clicking but you can also hear the tapping noise.

And it hasn't thrown any engine related codes.

Any opinions?
Lifters, HLA's or injectors ???
Thanks.

The tapping noise recording is gone?

I did listen to the recording earlier, and it’s sure like the valve clearance noise caused by bad hydraulic lash adjusters. Here’re some previous discussions here about bad (switchable) HLAs where they’re making tapping noise only on 2.5L NA with cylinder deactivation:

CX-5 engine rattle

2018 CX-5 GT Ticking

From the 2nd link we can see a Service Alert and a TSB related to this issue. The TSB is newer, released on 11/04/2020, where the repair procedure is keeping the engine rpm at 2000 rpm for 5 minutes to get rid of air bubbles in switchable HLAs for cylinder deactivation which amazes me.

 

[macker]

The tapping noise recording is gone?

I did listen to the recording earlier, and it’s sure like the valve clearance noise caused by bad hydraulic lash adjusters. Here’re some previous discussions here about bad (switchable) HLAs where they’re making tapping noise only on 2.5L NA with cylinder deactivation:

CX-5 engine rattle

2018 CX-5 GT Ticking

From the 2nd link we can see a Service Alert and a TSB related to this issue. The TSB is newer, released on 11/04/2020, where the repair procedure is keeping the engine rpm at 2000 rpm for 5 minutes to get rid of air bubbles in switchable HLAs for cylinder deactivation which amazes me.

I noticed the original recording was gone as well, but you can listen to mine....it's the same according to the OP.

And yes, at least in my case, the dealer is acknowledging it as not normal and possibly related to the most recent Service Alert (TSB).

 

[edmaz]

I've discussed/referenced the service alert on the HLA's and the service advisor acknowledged it. I also sent the service advisor my video clip and she shared it with one of their Techs and agreed this is not normal and *may* be related to the Mazda Service Alert mentioned.
...

Good to read that you have everything lined up and ready to roll. Now hopefully they will open it up, find that one or more of the switchable HLAs have failed, and resolve the issue by swapping them out.

 

[yrwei52]

that's a lifter tick, not injector.

Yes.

these lifters are hydraulic so they need oil pressure. sometimes oil doesn't flow with good pressure. i've seen this on many 2.5. especially 17/18 2.5s. it comes and goes.

Yeah the oil pressure comes and goes feeding the switchable HLAs on cylinder #1 and #4. But the 2.5L NA in 2017 CX-5 doesn’t have switchable HLAs used by cylinder deactivation.

it's not a big issue really.

Really? Only if you don’t want to keep your CX-5 for long term.

if dealer can replicate then they can replace the lifter. if not and it happens more frequently then an engine flush may help clear the passage ways. but it should go away after a day or 2.

HLA replacement is an expensive job if the car owner doesn’t have the warranty. Engine flush? Even the related TSB issued by Mazda doesn’t say that. Mazda recommends keeping the engine rpm at 2000 rpm for 5 minutes to clean up air bubbles in switchable HLAs.

 

[yrwei52]

I noticed the original recording was gone as well, but you can listen to mine....it's the same according to the OP.

And yes, at least in my case, the dealer is acknowledging it as not normal and possibly related to the most recent Service Alert (TSB).

Listened and yes the same tapping noise caused by failing (switchable) HLAs like many others.

 

[Jack Rabbit]

Good to read that you have everything lined up and ready to roll. Now hopefully they will open it up, find that one or more of the switchable HLAs have failed, and resolve the issue by swapping them out.

They won't touch it unless they can hear it while they have the vehicle.
Maybe Macker can leave his for a week, that is if they allow him to leave it in their lot that long. Hopefully Macker has better luck.

 

[macker]

They won't touch it unless they can hear it while they have the vehicle.
Maybe Macker can leave his for a week, that is if they allow him to leave it in their lot that long. Hopefully Macker has better luck.

Car will be left @ Mazda outside overnight. Looking like I'll have to reschedule as the forecast is calling for some mild weather this coming week. Following week looks to be colder again. I'll provide an update once Mazda has checked it out after a cold morning start.

IF the valve HLA's are the problem, was it because of a bad batch of them or perhaps they have re-designed them to fix the issue? Are there other consequences (other then the annoying noise) to not replacing these, i.e. damage to other engine components or cause excessive engine wear, etc.

Like everyone, I want a permanent fix and not something that's going to require another trip to a dealer/shop down the road for replacement....again.

 

[Jack Rabbit]

Car will be left @ Mazda outside overnight. Looking like I'll have to reschedule as the forecast is calling for some mild weather this coming week. Following week looks to be colder again. I'll provide an update once Mazda has checked it out after a cold morning start.

IF the valve HLA's are the problem, was it because of a bad batch of them or perhaps they have re-designed them to fix the issue? Are there other consequences (other then the annoying noise) to not replacing these, i.e. damage to other engine components or cause excessive engine wear, etc.

Like everyone, I want a permanent fix and not something that's going to require another trip to a dealer/shop down the road for replacement....again.

If you have a spare car, see if you can leave the CX-5 for a week and have them start it everyday.

 

[edmaz]

....
IF the valve HLA's are the problem, was it because of a bad batch of them or perhaps they have re-designed them to fix the issue?

This explanation is direct from Mazda in their TSB:
The tapping noise may be caused by the switchable hydraulic lash adjuster (HLA), which may not work properly due to air bubbles accumulated in the oil passage in it. To eliminate this concern, the switchable HLA has been modified for increased oil supply to reduce air bubbles in the oil passage.

And that's what's so unsettling to me about this whole thing. They've admitted that these HLAs have an issue, and have modified them to allow more oil flow. So where does that leave all of us who have 8 of these suckers in our engines, all of them potential candidates for becoming trashed by air bubbles. And there has so far been no explanation whatsoever about how and why these mysterious air bubbles become permanent residents inside of the HLA. This is the reason I asked you all of those questions - trying to find out if there's any specific reason for the air bubbles forming and, more importantly, what (if anything) can be done to prevent this from happening.

Are there other consequences (other then the annoying noise) to not replacing these, i.e. damage to other engine components or cause excessive engine wear, etc.

The jury is still out on that, awaiting additional data. However, the information that @Trzebs posted about his engine's HLA/noise issue, seemed to be fairly conclusive that something beyond the noise did happen to cylinder #4. Unfortunately, he did not provide anything further about what that turned out to be. In fairness, perhaps he just had the HLA replaced, and didn't pursue the additional problem.

Like everyone, I want a permanent fix and not something that's going to require another trip to a dealer/shop down the road for replacement....again.

One thing that some of us here have been kicking around, is the idea that all 8 of the switchable HLAs should be replaced, whenever the engine is opened up to perform this repair. The description in the TSB seems to be saying that only those HLAs identified as being defective are to be replaced, although we have no way of knowing what's actually happening with these repairs.

If they do find one or more defective HLAs in your engine, I recommend that you try to push hard for all of them to be replaced, unless of course they tell you up front that's what they will be doing. That idea might not fly, but perhaps Mazda will eventually buckle, if you keep reading what they wrote in their own TSB back to them.

 

[Jack Rabbit]

This explanation is direct from Mazda in their TSB:
The tapping noise may be caused by the switchable hydraulic lash adjuster (HLA), which may not work properly due to air bubbles accumulated in the oil passage in it. To eliminate this concern, the switchable HLA has been modified for increased oil supply to reduce air bubbles in the oil passage.

And that's what's so unsettling to me about this whole thing. They've admitted that these HLAs have an issue, and have modified them to allow more oil flow. So where does that leave all of us who have 8 of these suckers in our engines, all of them potential candidates for becoming trashed by air bubbles. And there has so far been no explanation whatsoever about how and why these mysterious air bubbles become permanent residents inside of the HLA. This is the reason I asked you all of those questions - trying to find out if there's any specific reason for the air bubbles forming and, more importantly, what (if anything) can be done to prevent this from happening.


The jury is still out on that, awaiting additional data. However, the information that @Trzebs posted about his engine's HLA/noise issue, seemed to be fairly conclusive that something beyond the noise did happen to cylinder #4. Unfortunately, he did not provide anything further about what that turned out to be. In fairness, perhaps he just had the HLA replaced, and didn't pursue the additional problem.



One thing that some of us here have been kicking around, is the idea that all 8 of the switchable HLAs should be replaced, whenever the engine is opened up to perform this repair. The description in the TSB seems to be saying that only those HLAs identified as being defective are to be replaced, although we have no way of knowing what's actually happening with these repairs.

If they do find one or more defective HLAs in your engine, I recommend that you try to push hard for all of them to be replaced, unless of course they tell you up front that's what they will be doing. That idea might not fly, but perhaps Mazda will eventually buckle, if you keep reading what they wrote in their own TSB back to them.

At the point, they have the head busted open, I would push for all to be replaced and if they balk, maybe consider paying additional cost for the extra HLA's and labor to replace the additional units. Shouldn't be too much more.

The problem is getting them to even pop the head off & check.
Unless they can hear it.

Who knows how much damage is occuring in the meantime when there is no noise, is it possible damage done because of insufficient oil...maybe quiet damage?

 

[macker]

If you have a spare car, see if you can leave the CX-5 for a week and have them start it everyday.

I do have another car, but the issue is pretty repeatable, especially when it's cold and sits outside overnight. I'd like to limit the amount of time it sits in the dealer lot as much as possible.

 

[macker]

This explanation is direct from Mazda in their TSB:
The tapping noise may be caused by the switchable hydraulic lash adjuster (HLA), which may not work properly due to air bubbles accumulated in the oil passage in it. To eliminate this concern, the switchable HLA has been modified for increased oil supply to reduce air bubbles in the oil passage.

And that's what's so unsettling to me about this whole thing. They've admitted that these HLAs have an issue, and have modified them to allow more oil flow. So where does that leave all of us who have 8 of these suckers in our engines, all of them potential candidates for becoming trashed by air bubbles. And there has so far been no explanation whatsoever about how and why these mysterious air bubbles become permanent residents inside of the HLA. This is the reason I asked you all of those questions - trying to find out if there's any specific reason for the air bubbles forming and, more importantly, what (if anything) can be done to prevent this from happening.


The jury is still out on that, awaiting additional data. However, the information that @Trzebs posted about his engine's HLA/noise issue, seemed to be fairly conclusive that something beyond the noise did happen to cylinder #4. Unfortunately, he did not provide anything further about what that turned out to be. In fairness, perhaps he just had the HLA replaced, and didn't pursue the additional problem.



One thing that some of us here have been kicking around, is the idea that all 8 of the switchable HLAs should be replaced, whenever the engine is opened up to perform this repair. The description in the TSB seems to be saying that only those HLAs identified as being defective are to be replaced, although we have no way of knowing what's actually happening with these repairs.

If they do find one or more defective HLAs in your engine, I recommend that you try to push hard for all of them to be replaced, unless of course they tell you up front that's what they will be doing. That idea might not fly, but perhaps Mazda will eventually buckle, if you keep reading what they wrote in their own TSB back to them.

Thanks for the excerpt describing the cause. I didn't see that in the one I have....maybe I've got the older version (Service Alert No.: SA-012/19). If you have the updated one and can attach....that would be great.

I haven't yet really noticed the issue outside of the cold start up, so perhaps the temperature outside is a big contributor in the formation and sticking of air bubbles in the HLA's?

The fact they re-designed these, and considering the original ones can impede oil flow....that's a scary thought to me. Might be ok in the short term, but long term, I could see engine damage or excessive oil burning or both both.

I agree with your thoughts around replacing all 8, vs. just the pair sounding noisy, especially in light of the fact they know they weren't right out of the factory. I'll definitely push them as much as possible to do them all if they do find some noisy ones.

 

[yrwei52]

Thanks for the excerpt describing the cause. I didn't see that in the one I have....maybe I've got the older version (Service Alert No.: SA-012/19). If you have the updated one and can attach....that would be great.

Yes the TSB does mentioned the air bubble thing. See my post #43 above with the link to the Service Alert and the newer TSB for the issue.

 

[edmaz]

Thanks for the excerpt describing the cause. I didn't see that in the one I have....maybe I've got the older version (Service Alert No.: SA-012/19). If you have the updated one and can attach....that would be great.

The link for the most recent TSB is in post #15 of this thread.

I haven't yet really noticed the issue outside of the cold start up, so perhaps the temperature outside is a big contributor in the formation and sticking of air bubbles in the HLA's?

Well this whole HLA air bubble thing is certainly a big mystery, and I have to admit that your feedback on vehicle maintenance and operation has basically eliminated a couple of my previous suspects. And the theory of cold weather being the primary cause of the bubbles, runs into the obvious question of why this problem hasn't been happening more often in Canada and the upper US.

And most other theories run into the same question of why it isn't being reported more frequently. IDK, perhaps there is more of this happening and the owners just aren't picking up on it. Time will tell about that I guess. In any case, I'm really interested to see if they find one or more problem HLAs in your engine, or if they discover some other reason for the noise.

 

[macker]

The link for the most recent TSB is in post #15 of this thread.


Well this whole HLA air bubble thing is certainly a big mystery, and I have to admit that your feedback on vehicle maintenance and operation has basically eliminated a couple of my previous suspects. And the theory of cold weather being the primary cause of the bubbles, runs into the obvious question of why this problem hasn't been happening more often in Canada and the upper US.

And most other theories run into the same question of why it isn't being reported more frequently. IDK, perhaps there is more of this happening and the owners just aren't picking up on it. Time will tell about that I guess. In any case, I'm really interested to see if they find one or more problem HLAs in your engine, or if they discover some other reason for the noise.

I think that may be it; people are just shrugging it off because it's not always present and/or they are inside their car when they start it and not aware of it so much. Not sure how else this can be explained, since we are led to believe the the HLA's had to be re-designed to resolve the issue?

 

[edmaz]

... and/or they are inside their car when they start it and not aware of it so much. ....

Yes, what you wrote above is likely a very key factor.

At the time when your vehicle is making the most noise, how much less noticeable would you say it is when you're inside the cabin with the door closed, versus standing outside and listening to it from there?

Would you say that the majority of drivers, who are probably much less attuned to this stuff than most of the folks on this forum, might not even realize there's any abnormal noise at all?

 

[Jack Rabbit]

Yes, what you wrote above is likely a very key factor.

At the time when your vehicle is making the most noise, how much less noticeable would you say it is when you're inside the cabin with the door closed, versus standing outside and listening to it from there?

Would you say that the majority of drivers, who are probably much less attuned to this stuff than most of the folks on this forum, might not even realize there's any abnormal noise at all?

Yes the CX-5 is a ventriliquist.
Can't hear it that much when windows are closed. 1st time it happened, when sitting at idle at traffic light, thought it was car behind me until I opened my window and was like wtf. Next day it happened again while I was outside my vehicle.

 

[macker]

Yes, what you wrote above is likely a very key factor.

At the time when your vehicle is making the most noise, how much less noticeable would you say it is when you're inside the cabin with the door closed, versus standing outside and listening to it from there?

Would you say that the majority of drivers, who are probably much less attuned to this stuff than most of the folks on this forum, might not even realize there's any abnormal noise at all?

Can't say I've really heard it inside the car, unless I shut off the radio, heater, etc., then it's more noticeable. Would it cause the avg. owner to be concerned? IMO, I'd say no.