Engine Ticking Noise
05-24-2024, 02:21 PM
#436
Rennlist Member
For those who are too lazy to click the TSB link:
”In contrast to 718 model line vehicles with 4 cylinder Boxer engines, piezo injection valves are used instead of the conventional solenoid injection valves for derivatives with 4.0-liter flat-6 engine.
Piezo injection valves have a directly actuated and outwardly opening nozzle in conjunction with the piezo actuator, enabling extremely short switching times (up to four times shorter than with solenoid valves), making high-precision fuel dosing possible. With up to five injections per working cycle, highly flexible injection technologies are implemented, optimizing combustion and ultimately reducing fuel consumption.
Compared to motors with solenoid valve injectors, the piezo injection system is characterized by a metallic impact noise in the range of 3 kHz. This frequency range is perceived particularly intensely by humans.
Particularly in the lower load and engine speed range, when engine and driving noises move into the back- ground, the injection system’s impact noise can be perceived as dominant. Operating states such as idling, starting off and manoeuvring are particularly noticeable. As the load and engine speed increases, the sound of the fuel injectors fades into the background due to the increased noise level of the engine, exhaust system as well as rolling and wind noises.
Propagation of sound waves is particularly encouraged by the installation position of the flat engine. Due to the low position in the vehicle, the sound radiates in the direction of the road and the wheel housing. The sound waves are reflected and diffused in the vehicle surroundings.
Efficiently absorbing sound via acoustic insulation in the engine compartment is difficult due to the center or rear engine configuration compared to the front engine. In addition, some vehicles are also operated on the race circuit. The resulting high thermal loads make a complete acoustic engine compartment encapsulation impossible.
On 718 model line vehicles with a 4.0-liter flat-6 engine, piezo injection valves were deliberately chosen, as the emission benefits outweigh possible acoustic drawbacks while at the same time maintaining high specific power.”
”In contrast to 718 model line vehicles with 4 cylinder Boxer engines, piezo injection valves are used instead of the conventional solenoid injection valves for derivatives with 4.0-liter flat-6 engine.
Piezo injection valves have a directly actuated and outwardly opening nozzle in conjunction with the piezo actuator, enabling extremely short switching times (up to four times shorter than with solenoid valves), making high-precision fuel dosing possible. With up to five injections per working cycle, highly flexible injection technologies are implemented, optimizing combustion and ultimately reducing fuel consumption.
Compared to motors with solenoid valve injectors, the piezo injection system is characterized by a metallic impact noise in the range of 3 kHz. This frequency range is perceived particularly intensely by humans.
Particularly in the lower load and engine speed range, when engine and driving noises move into the back- ground, the injection system’s impact noise can be perceived as dominant. Operating states such as idling, starting off and manoeuvring are particularly noticeable. As the load and engine speed increases, the sound of the fuel injectors fades into the background due to the increased noise level of the engine, exhaust system as well as rolling and wind noises.
Propagation of sound waves is particularly encouraged by the installation position of the flat engine. Due to the low position in the vehicle, the sound radiates in the direction of the road and the wheel housing. The sound waves are reflected and diffused in the vehicle surroundings.
Efficiently absorbing sound via acoustic insulation in the engine compartment is difficult due to the center or rear engine configuration compared to the front engine. In addition, some vehicles are also operated on the race circuit. The resulting high thermal loads make a complete acoustic engine compartment encapsulation impossible.
On 718 model line vehicles with a 4.0-liter flat-6 engine, piezo injection valves were deliberately chosen, as the emission benefits outweigh possible acoustic drawbacks while at the same time maintaining high specific power.”
The following 2 users liked this post by UncleDude:
subwoofer (05-24-2024),
tigerhonaker (05-25-2024)
05-24-2024, 02:51 PM
#437
Rennlist Member
Good to read Porsche's technical bulletin. For some, it is another adorable idiosyncrasy of the 4 liter. Or a mere annoyance to tolerate for others.
The following users liked this post:
tigerhonaker (05-25-2024)
05-24-2024, 02:56 PM
#438
what you hear in you video examples IMG_1395 and IMG_1396 is the normal ticking of two valves whose clearances are temporarily increased for a short period of time. Reason is, that the springs of opened valves have compressed the assigned hydraulic lifters by a small - but absolutely required - leakage along the annular space between piston and cylinder of the hydraulic lifters, during the engine was stopped.
That has nothing in common with the complained permanent ticking as measured for example in my post # 151 in this thread, which does not disappear but increases more and more, when the engine becomes warm.
On the contrary, your 4 litre natural aspired engine is one of the smoothest running I ever heared.
05-24-2024, 03:07 PM
#439
Rennlist Member
Hi Subwoofer,
what you hear in you video examples IMG_1395 and IMG_1396 is the normal ticking of two valves whose clearances are temporarily increased for a short period of time. Reason is, that the springs of opened valves have compressed the assigned hydraulic lifters by a small - but absolutely required - leakage along the annular space between piston and cylinder of the hydraulic lifters, during the engine was stopped.
That has nothing in common with the complained permanent ticking as measured for example in my post # 151 in this thread, which does not disappear but increases more and more, when the engine becomes warm.
On the contrary, your 4 litre natural aspired engine is one of the smoothest running I ever heared.
what you hear in you video examples IMG_1395 and IMG_1396 is the normal ticking of two valves whose clearances are temporarily increased for a short period of time. Reason is, that the springs of opened valves have compressed the assigned hydraulic lifters by a small - but absolutely required - leakage along the annular space between piston and cylinder of the hydraulic lifters, during the engine was stopped.
That has nothing in common with the complained permanent ticking as measured for example in my post # 151 in this thread, which does not disappear but increases more and more, when the engine becomes warm.
On the contrary, your 4 litre natural aspired engine is one of the smoothest running I ever heared.
05-25-2024, 07:08 AM
#440
sorry, but it's just the same with your examples in your post #331 in this thread.
Sound analysis (not subjective ear impressions !) doesn't show complained tickings as detected in my soundfile #151.
Please compare.
What you hear and have recorded is the normal sound of a not acoustically covered natural aspired 6 cylinder engine, may be amplified from the bottom, if the car is standing on solid ground or by wall reflections of the sound.
Your car is a good example for a not ticking engine (differing from mine in the beginning).
Congratulations !
05-25-2024, 08:45 AM
#441
Rennlist Member
Hi Subwoofer,
sorry, but it's just the same with your examples in your post #331 in this thread.
Sound analysis (not subjective ear impressions !) doesn't show complained tickings as detected in my soundfile #151.
Please compare.
What you hear and have recorded is the normal sound of a not acoustically covered natural aspired 6 cylinder engine, may be amplified from the bottom, if the car is standing on solid ground or by wall reflections of the sound.
Your car is a good example for a not ticking engine (differing from mine in the beginning).
Congratulations !
sorry, but it's just the same with your examples in your post #331 in this thread.
Sound analysis (not subjective ear impressions !) doesn't show complained tickings as detected in my soundfile #151.
Please compare.
What you hear and have recorded is the normal sound of a not acoustically covered natural aspired 6 cylinder engine, may be amplified from the bottom, if the car is standing on solid ground or by wall reflections of the sound.
Your car is a good example for a not ticking engine (differing from mine in the beginning).
Congratulations !
05-25-2024, 10:11 AM
#442
you can't download the .AVI - videoclips #151 and #440 ?
That's a pity as I'm convinced that comparison would assure you your car sounding pretty good.
As I reported, ticking of my car has completely disappeared after about 10.000 miles. And it's not the injectors (that must be at least 6 sound events per camshaft revolution) but one sticking hydraulic lifter, which has become free now (as it is with many GTS 4.0 I've heared and analyzed, but not with all and particularly not with yours).
.AVI runs on PC and ANDROID (-> don't convert !), don't know about IOS. Could be you have a friend with a PC or ANDROID device ?
Comparison of the soundfiles may be advantageous for you to increase enjoyment for your great car.
07-02-2024, 07:14 PM
#443
A late update, dealer was as expected useless and didn't do anything.
Perhaps if any vendors are watching this thread, a good opportunity for an aftermarket solution? Some insulation around the fuel pump or something?
Perhaps if any vendors are watching this thread, a good opportunity for an aftermarket solution? Some insulation around the fuel pump or something?
The following users liked this post:
SpyderSenseOC (07-03-2024)
07-02-2024, 10:01 PM
#444
Rennlist Member
There is a solution to this ticking noise, and it’s in the form of an aftermarket exhaust. You just gotta give your ears something more pleasing to look forward to, and stop chasing a so called fix… it ain’t comin’
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tigerhonaker (07-03-2024)
07-03-2024, 12:05 PM
#445
The fuel pump is directly behind the driver's ear in the engine bay. I am not an engineer, but I imagine adding some sort of insulation there wouldn't hurt too much as it's an area that doesn't really get airflow and probably isn't a huge thermal concern...
07-03-2024, 12:09 PM
#446
Rennlist Member
I now run the Newest V2 version of the SOUL Performance "Rear-Exhaust-System" and I don't hear the annoying "Ticking-Sound" at all.
Honestly though I don't actually try to hear the "Ticking-Noise" anyway .............
Terry
07-03-2024, 12:12 PM
#447
RL Community Team
Rennlist Member
Rennlist Member
07-03-2024, 12:15 PM
#448
It is a shame because it's the only negative about the car I can think of. I can put up with it, and I do think an aftermarket solution is a possibility. It plagues 992's as well (but since the engine is placed in a different location/direction, it is less noticeable).
07-03-2024, 12:27 PM
#449
Rennlist Member
Hate to say it but it's there, perhaps it just does not bother you as much.
It is a shame because it's the only negative about the car I can think of. I can put up with it, and I do think an aftermarket solution is a possibility. It plagues 992's as well (but since the engine is placed in a different location/direction, it is less noticeable).
It is a shame because it's the only negative about the car I can think of. I can put up with it, and I do think an aftermarket solution is a possibility. It plagues 992's as well (but since the engine is placed in a different location/direction, it is less noticeable).
justince,
Hate to say it but it's there, perhaps it just does not bother you as much.
Hate to say it but it's there, perhaps it just does not bother you as much.
Your right if I tried to hear the "Ticking" I have No-Doubt I could.
It's just not thankfully noticeable with me running the, SOUL, V2 rear-exhaust-system, SOUL, ceramic-coated (Performance) OAP.
Also I have and use daily the Cargraphics valve-controller.
I can understand owners like yourself that don't like the "Ticking" nor do you or others want to put up with it.
Terry
