2022 Tahoe engine tick (recording). Please help identify possible root cause.

[tahoe_rst]

Hi all,

My new Tahoe 6.2 engine ticking, less than 2k km mileage.
Those who had experience with lifters, HPFP, etc, please help me to diagnose it.
I would like to understand if that is something I should be worried about or it is normal engine operation sound.

Here are some additional details for you to diagnose better:
1. There is no tick on cold start and within next 7-10 mins after start.
2. I can hear the ticking noise only on warm engine (mainly after 20 min drive). After ticking noise started on warm engine it doesn't go away unless you park the car for 5-6 hours.
3. I can hear it mainly from the front left wheel area and even more clear I can hear it from the bottom of the engine (under the driver's door)
4. The ticking noise doesn't sound like a loud knocking (like in the videos when lifter failed). It sounds much lighter than that, but at the same time it sounds much louder than injector noise.
5. The ticking noise appears mainly when idling. When you slightly press and hold the gas it disappears. But when you rev it further, it is still there but the volume of ticking noise is getting lower and it gets completely not recognisable at RPM>2000.


The potential scenarios in my mind:
1. Lifter issue (the worst)
2. High Pressure Fuel Pump issue
3. Normal lifter operation sound?
4. Normal HPFP operation sound?
4. Anything else?

Here is the recording of the ticking sound on hot engine (after 40 min drive).
Here is the recording of the cold engine sound (I don't hear any ticking noise)

Please share you thought, appreciate your support.

 

[DuraYuk]

Hi all,

My new Tahoe 6.2 engine ticking, less than 2k km mileage.
Those who had experience with lifters, HPFP, etc, please help me to diagnose it.
I would like to understand if that is something I should be worried about or it is normal engine operation sound.

Here are some additional details for you to diagnose better:
1. There is no tick on cold start and within next 7-10 mins after start.
2. I can hear the ticking noise only on warm engine (mainly after 20 min drive). After ticking noise started on warm engine it doesn't go away unless you park the car for 5-6 hours.
3. I can hear it mainly from the front left wheel area and even more clear I can hear it from the bottom of the engine (under the driver's door)
4. The ticking noise doesn't sound like a loud knocking (like in the videos when lifter failed). It sounds much lighter than that, but at the same time it sounds much louder than injector noise.
5. The ticking noise appears mainly when idling. When you slightly press and hold the gas it disappears. But when you rev it further, it is still there but the volume of ticking noise is getting lower and it gets completely not recognisable at RPM>2000.


The potential scenarios in my mind:
1. Lifter issue (the worst)
2. High Pressure Fuel Pump issue
3. Normal lifter operation sound?
4. Normal HPFP operation sound?
4. Anything else?

Here is the recording of the sound.

Please share you thought, appreciate your support.

Sounds like injectors to me. Its hard to discern specific sounds via phone audio. I will say tho these forums have created a whole subset of owners who think their cars are gonna blow up in short order.

With that said maybe take it to the dealer and have them listen? Or perhaps wait for it to blow then fix it?

I was a tech for a long time and when i buy a car with warranty that's what i use until its my turn to work.

 

[Geotrash]

Hi all,

My new Tahoe 6.2 engine ticking, less than 2k km mileage.
Those who had experience with lifters, HPFP, etc, please help me to diagnose it.
I would like to understand if that is something I should be worried about or it is normal engine operation sound.

Here are some additional details for you to diagnose better:
1. There is no tick on cold start and within next 7-10 mins after start.
2. I can hear the ticking noise only on warm engine (mainly after 20 min drive). After ticking noise started on warm engine it doesn't go away unless you park the car for 5-6 hours.
3. I can hear it mainly from the front left wheel area and even more clear I can hear it from the bottom of the engine (under the driver's door)
4. The ticking noise doesn't sound like a loud knocking (like in the videos when lifter failed). It sounds much lighter than that, but at the same time it sounds much louder than injector noise.
5. The ticking noise appears mainly when idling. When you slightly press and hold the gas it disappears. But when you rev it further, it is still there but the volume of ticking noise is getting lower and it gets completely not recognisable at RPM>2000.


The potential scenarios in my mind:
1. Lifter issue (the worst)
2. High Pressure Fuel Pump issue
3. Normal lifter operation sound?
4. Normal HPFP operation sound?
4. Anything else?

Here is the recording of the sound.

Please share you thought, appreciate your support.

To my ear, that sounds like a single lifter tapping pretty good, but not as loud as I've heard many of them after failure.

 

[tahoe_rst]

To my ear, that sounds like a single lifter tapping pretty good, but not as loud as I've heard many of them after failure.

Hi Dave, thank you for comments.
Any idea why lifter is quiet on cold engine and noisy on hot engine?

 

[Geotrash]

Hi Dave, thank you for comments.
Any idea why lifter is quiet on cold engine and noisy on hot engine?

It’s only an educated guess, but it’s not terribly uncommon for a hydraulic lifter that has poor clearances internally to bleed off pressure faster when the engine is hot, and tick. My guess is that for whatever reason, that lifter is not able to maintain proper lash when the engine is warm and the oil is thinner.

 

[B-train]

It's hard to tell, but it sounds similar to an exhaust manifold leak to me. I do hear the internal stuff as well. I know on my 17 I can hear injector and normal valvetrain operation. You said it goes away with throttle? Have you tried to brake torque it with a little throttle in gear and see if it changes sound?

 

[DuraYuk]

It's hard to tell, but it sounds similar to an exhaust manifold leak to me. I do hear the internal stuff as well. I know on my 17 I can hear injector and normal valvetrain operation. You said it goes away with throttle? Have you tried to brake torque it with a little throttle in gear and see if it changes sound?

Yup. Could be a exhaust leak. Either at manifold or where the Y joins the rest.

I do think most are rooting for lifter issue tho. Transmission slipping = lifters, misfire = lifters, injector codes = lifters, coins shifting in cup holder = lifters, 21+ key fob not working = lifters. Engine won't start after remote start = lifters, lol, smh.

Hopefully it is something simple. That video is horrible. Go video the best running engine ever and listen to the audio. Sounds catastrophic.

 

[Geotrash]

Yup. Could be a exhaust leak. Either at manifold or where the Y joins the rest.

I do think most are rooting for lifter issue tho. Transmission slipping = lifters, misfire = lifters, injector codes = lifters, coins shifting in cup holder = lifters, 21+ key fob not working = lifters. Engine won't start after remote start = lifters, lol, smh.

Hopefully it is something simple. That video is horrible. Go video the best running engine ever and listen to the audio. Sounds catastrophic.

If the leak were at the y-pipe then the frequency would be 2x crankshaft rotation instead of 1/2 crankshaft rotation as it currently is. If it's an exhaust leak, then it's at the exhaust manifold on a single exhaust port and wouldn't disappear with throttle.

Another clue that points toward a lifter and my theory is plausible, is that it goes away with throttle. Faster cam rotation = less time for the lifter to bleed off oil pressure internally = maintains lash at higher RPMs. Either way, I don't think it's a significant issue at this point. If it were mine, I would pay attention to it over time and see if it worsens. I doubt that failure is imminent.

I'm not "rooting" for anything - just trying to be helpful.

 

[DuraYuk]

If the leak were at the y-pipe then the frequency would be 2x crankshaft rotation instead of 1/2 crankshaft rotation as it currently seems to be. If it's an exhaust leak, then it's at the exhaust manifold on a single exhaust port and wouldn't disappear with throttle.

Another clue that points toward a lifter and my theory is plausible, is that it goes away with throttle. Faster cam rotation = less time for the lifter to bleed off oil pressure internally = maintains lash at higher RPMs. I'm not "rooting" for anything - just trying to be helpful.

Lets root for the lifter then. Exhaust leaks can close and open due to temperature. And you have some magic ears man cuz listening to the video its hard to get that kind of information.

Exhaust leaks can disappear with throttle. As they can with temp changes.

All theories are plausible.

Hopefully it's not a lifter but if it is not the end of the world. Id still take it in so someone can actually listen instead of trying to diagnose over a video.

Edit: I listened again and holy smokes Batman. Hard to say cuz nothing sticks out to me. Maybe my phone just isn't cutting it.

 

[Geotrash]

Lets root for the lifter then. Exhaust leaks can close and open due to temperature. And you have some magic ears man cuz listening to the video its hard to get that kind of information.

Exhaust leaks can disappear with throttle. As they can with temp changes.

All theories are plausible.

Hopefully it's not a lifter but if it is not the end of the world. Id still take it in so someone can actually listen instead of trying to diagnose over a video.

Edit: I listened again and holy smokes Batman. Hard to say cuz nothing sticks out to me. Maybe my phone just isn't cutting it.

Try it with headphones on. I'm on a laptop with Bose headphones - much easier to discern. On the cold engine video all I hear is typical direct injector noise. On the warm engine video it's much more prevalent as he moves the camera to beneath the bumper.

Another possibility is the vacuum pump. Some are reporting a tapping similar to a lifter noise and at the same frequency, as a failure mode for it.