Odd rev-correlated intake-whine. Is this normal?
11-18-2019, 02:26 AM
#76
Racer
To those GT4 owners who have experienced the mind numbing “cricket” sounding whine: After two trips to two dealers and a box of Dynamat placed in various areas, I believe I found the problem. Porsche has done a relatively good job of insulating the engine except for one area which happens to allow for this obnoxious sound caught on audio throughout this thread. If you remove the plastic cover behind the seat/just behind the doors where the seat belt tensioner resides, you will find that there is NO insulation there (at least on my Nov ‘15 build). To top that, there is a space around the seat belt mechanism leading directly to the uninsulated sheet metal around the intake. I found this by placing a thick blanket behind the seat and against the back of the door.
The fix is to simply fill that cavity and the surrounding area with insulation material. I used Dynamat and some microfiber towels. There is still a faint “Porsche” whine that is certainly acceptable, but the mind numbing, high pitched “cricket” sound (likely intake valve noise) is gone. The car is substantially more pleasurable to drive when not at the track. Although I am rather new to this thread and to Porsche ownership, I am not new to GT type sports cars or race cars. GT stands for Grand Touring which should translate to a “car that one should enjoy in pleasure and spirited driving”. Now that this noise is rectified, this GT4 is pleasurable everywhere.
The fix is to simply fill that cavity and the surrounding area with insulation material. I used Dynamat and some microfiber towels. There is still a faint “Porsche” whine that is certainly acceptable, but the mind numbing, high pitched “cricket” sound (likely intake valve noise) is gone. The car is substantially more pleasurable to drive when not at the track. Although I am rather new to this thread and to Porsche ownership, I am not new to GT type sports cars or race cars. GT stands for Grand Touring which should translate to a “car that one should enjoy in pleasure and spirited driving”. Now that this noise is rectified, this GT4 is pleasurable everywhere.
11-18-2019, 10:17 AM
#77
Crickets
What the sound is related to is the cam timing and valves. The “cricket” sound gets substantially louder or softer whether going up through the rev range or down at about 3725rpm. That is apparently when the cam timing changes the valve lift.
The uninsulated area behind the seat where the seat belt tensioner mounts is directly above the intake on the side of the car. The sound of the valves literally travels into that cavity that is not insulated. You can hear the sound on throttle standing still, but it seems louder under load.
The uninsulated area behind the seat where the seat belt tensioner mounts is directly above the intake on the side of the car. The sound of the valves literally travels into that cavity that is not insulated. You can hear the sound on throttle standing still, but it seems louder under load.
09-15-2020, 05:36 PM
#78
I got a 2020 GTS 4.0 and have similar noise.
In my case it is noticeable between 2500-4500 RPM range, and it is related to RPM. It's a little high pitched, almost like a super charger.
Not sure if this is the same case or not.
Any conclusion on this? Nothing to worry about I guess?
But it is annoying if I'm honest. I cruise in that RPM range often.
It's going to be my last Porsche I have decided. Next car R8 V10 RWD.
In my case it is noticeable between 2500-4500 RPM range, and it is related to RPM. It's a little high pitched, almost like a super charger.
Not sure if this is the same case or not.
Any conclusion on this? Nothing to worry about I guess?
But it is annoying if I'm honest. I cruise in that RPM range often.
It's going to be my last Porsche I have decided. Next car R8 V10 RWD.
09-16-2020, 08:27 AM
#79
Drifting
Thread Starter
What the sound is related to is the cam timing and valves. The “cricket” sound gets substantially louder or softer whether going up through the rev range or down at about 3725rpm. That is apparently when the cam timing changes the valve lift.
The uninsulated area behind the seat where the seat belt tensioner mounts is directly above the intake on the side of the car. The sound of the valves literally travels into that cavity that is not insulated. You can hear the sound on throttle standing still, but it seems louder under load.
The uninsulated area behind the seat where the seat belt tensioner mounts is directly above the intake on the side of the car. The sound of the valves literally travels into that cavity that is not insulated. You can hear the sound on throttle standing still, but it seems louder under load.
Thanks for this info, Proracing! To be honest, I’d forgotten all about the sound just by getting used to it, I suppose. And Soul headers didn’t hurt any either.
But when I get back in town I’ll try the same thing you’ve done and see if it improves the experience.
06-16-2021, 04:21 PM
#80
To those GT4 owners who have experienced the mind numbing “cricket” sounding whine: After two trips to two dealers and a box of Dynamat placed in various areas, I believe I found the problem. Porsche has done a relatively good job of insulating the engine except for one area which happens to allow for this obnoxious sound caught on audio throughout this thread. If you remove the plastic cover behind the seat/just behind the doors where the seat belt tensioner resides, you will find that there is NO insulation there (at least on my Nov ‘15 build). To top that, there is a space around the seat belt mechanism leading directly to the uninsulated sheet metal around the intake. I found this by placing a thick blanket behind the seat and against the back of the door.
The fix is to simply fill that cavity and the surrounding area with insulation material. I used Dynamat and some microfiber towels. There is still a faint “Porsche” whine that is certainly acceptable, but the mind numbing, high pitched “cricket” sound (likely intake valve noise) is gone. The car is substantially more pleasurable to drive when not at the track. Although I am rather new to this thread and to Porsche ownership, I am not new to GT type sports cars or race cars. GT stands for Grand Touring which should translate to a “car that one should enjoy in pleasure and spirited driving”. Now that this noise is rectified, this GT4 is pleasurable everywhere.
The fix is to simply fill that cavity and the surrounding area with insulation material. I used Dynamat and some microfiber towels. There is still a faint “Porsche” whine that is certainly acceptable, but the mind numbing, high pitched “cricket” sound (likely intake valve noise) is gone. The car is substantially more pleasurable to drive when not at the track. Although I am rather new to this thread and to Porsche ownership, I am not new to GT type sports cars or race cars. GT stands for Grand Touring which should translate to a “car that one should enjoy in pleasure and spirited driving”. Now that this noise is rectified, this GT4 is pleasurable everywhere.
08-20-2023, 02:25 PM
#81
Reviving an old one, but the mind numbing cricket sound has struck again! I’ve been monitoring this sound for months now - it sort of “became” more noticeable a few months ago. I’ve driven another GT4 and I could hear the sound, just not as pronounced. I was initially worried that my recent move to redline oil (rather than liquimoly) and 75w140 swepco transmission oil (rather than the standard 75w90) could have caused this, but it seems @Proracing findings have been to add insulation to this area behind the seat. Everything described so far is exactly how my car sounds.
Anyone share some photos or more details on where and how to add the insulation? I’d be very grateful.
Anyone share some photos or more details on where and how to add the insulation? I’d be very grateful.
08-21-2023, 10:37 AM
#82
Whining sound likely to be the air oil separator
Hey Guys,
I know first hand how irritating this sound can be!
I was told by a Porsche tech that it’s an air oil separator (AOS) vacuum pump related sound, hence the whining that increases with RPM.
There is a “new” AOS part number and dealer accessible information on this issue…according to my service manager. He had to research it for a day
I bought the “new” AOS and had it installed during my 6 year service. My subjective impression is about a 50-60% reduction in the volume of the whine, enough that I don’t hear it unless I focus on trying to pick it out from the overall sound of the engine.
This is the part number I was given by my service manager: 9A110704202
Hope this is helpful!
I know first hand how irritating this sound can be!
I was told by a Porsche tech that it’s an air oil separator (AOS) vacuum pump related sound, hence the whining that increases with RPM.
There is a “new” AOS part number and dealer accessible information on this issue…according to my service manager. He had to research it for a day
I bought the “new” AOS and had it installed during my 6 year service. My subjective impression is about a 50-60% reduction in the volume of the whine, enough that I don’t hear it unless I focus on trying to pick it out from the overall sound of the engine.
This is the part number I was given by my service manager: 9A110704202
Hope this is helpful!
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GT3FZS (01-26-2024)
08-21-2023, 12:01 PM
#83
Hey Guys,
I know first hand how irritating this sound can be!
I was told by a Porsche tech that it’s an air oil separator (AOS) vacuum pump related sound, hence the whining that increases with RPM.
There is a “new” AOS part number and dealer accessible information on this issue…according to my service manager. He had to research it for a day
I bought the “new” AOS and had it installed during my 6 year service. My subjective impression is about a 50-60% reduction in the volume of the whine, enough that I don’t hear it unless I focus on trying to pick it out from the overall sound of the engine.
This is the part number I was given by my service manager: 9A110704202
Hope this is helpful!
I know first hand how irritating this sound can be!
I was told by a Porsche tech that it’s an air oil separator (AOS) vacuum pump related sound, hence the whining that increases with RPM.
There is a “new” AOS part number and dealer accessible information on this issue…according to my service manager. He had to research it for a day
I bought the “new” AOS and had it installed during my 6 year service. My subjective impression is about a 50-60% reduction in the volume of the whine, enough that I don’t hear it unless I focus on trying to pick it out from the overall sound of the engine.
This is the part number I was given by my service manager: 9A110704202
Hope this is helpful!
08-21-2023, 02:06 PM
#84
AOS whine
I didn’t try anything else, because I was told by a Porsche technician(and an independent Porsche specialty shop that did the PPI on my car) that the sound was a vacuum pump sound related to the AOS. I lived with it until it was time for my 6 year service…when I figured it was a good opportunity to have them swap in the new AOS. I wasn’t aware of other GT4 owners reporting “no change” in the audible whine with the new pump. I feel confidant in my subjective response that there’s a 50-60-% reduction in the volume of the sound. The sound is not gone, but I think that’s because it’s an updated version of the same intrinsic mechanical device. I have some in car phone recording with the original pump that might capture the whine, and next weekend I’ll make a new phone recording and try to be consistent to the original variables.
08-21-2023, 02:17 PM
#85
I didn’t try anything else, because I was told by a Porsche technician(and an independent Porsche specialty shop that did the PPI on my car) that the sound was a vacuum pump sound related to the AOS. I lived with it until it was time for my 6 year service…when I figured it was a good opportunity to have them swap in the new AOS. I wasn’t aware of other GT4 owners reporting “no change” in the audible whine with the new pump. I feel confidant in my subjective response that there’s a 50-60-% reduction in the volume of the sound. The sound is not gone, but I think that’s because it’s an updated version of the same intrinsic mechanical device. I have some in car phone recording with the original pump that might capture the whine, and next weekend I’ll make a new phone recording and try to be consistent to the original variables.
08-21-2023, 03:27 PM
#86
I got the AOS from Suncoast Porsche in Florida. It was $175 and the labor is pricy at $550…my dealer said that a standard Cayman AOS swap is a couple hours and unfortunately the 981 GT4 swap is more involved at 4-6 hours. I’ll do my best to get the A to B videos next weekend
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DXB-GT4 (08-22-2023)
01-04-2024, 04:36 AM
#87
Hello All-
I am glad I am not the only person who thinks the rev-correlated whine is a substantial distraction from the driving experience of the GT4. I have been looking all over forums to find a complete story -- I have had my car since new, and do not recall hearing the sound during break-in period. However, over the past year, it has gotten quite annoying. I do know that the sound at least exists on another 718 GT4 I have driven. I do not think it is gear whine as you can sit in neutral, without the car moving and still hear the whine as the RPM surpass 1950 RPM - it sounds like it could be a pulley or tensioner. I have had the car evaluated by Porsche AND two independent shops. 2 of 3 suggest it is normal.....but I don't care if it is normal, I want to fix it. I know the previous 981 GT4 has an AOS recall, and I appreciate that this might also be related to the AOS. Does anyone have a recording they can post of the before and after?...I want to compare it with my vehicle. Can anyone else confirm that the new part number listed above does reduce that sound in more than the single case cited? I have already removed the sound symposer and added dynamat and mass-loaded vinyl, but the whine persists. Finally, if the 4.0L is a variant of the current 911 (992) motor, why doesn't the sound exist on that vehicle?
THANKS!
I am glad I am not the only person who thinks the rev-correlated whine is a substantial distraction from the driving experience of the GT4. I have been looking all over forums to find a complete story -- I have had my car since new, and do not recall hearing the sound during break-in period. However, over the past year, it has gotten quite annoying. I do know that the sound at least exists on another 718 GT4 I have driven. I do not think it is gear whine as you can sit in neutral, without the car moving and still hear the whine as the RPM surpass 1950 RPM - it sounds like it could be a pulley or tensioner. I have had the car evaluated by Porsche AND two independent shops. 2 of 3 suggest it is normal.....but I don't care if it is normal, I want to fix it. I know the previous 981 GT4 has an AOS recall, and I appreciate that this might also be related to the AOS. Does anyone have a recording they can post of the before and after?...I want to compare it with my vehicle. Can anyone else confirm that the new part number listed above does reduce that sound in more than the single case cited? I have already removed the sound symposer and added dynamat and mass-loaded vinyl, but the whine persists. Finally, if the 4.0L is a variant of the current 911 (992) motor, why doesn't the sound exist on that vehicle?
THANKS!
01-06-2024, 01:08 PM
#88
Hello All-
I am glad I am not the only person who thinks the rev-correlated whine is a substantial distraction from the driving experience of the GT4. I have been looking all over forums to find a complete story -- I have had my car since new, and do not recall hearing the sound during break-in period. However, over the past year, it has gotten quite annoying. I do know that the sound at least exists on another 718 GT4 I have driven. I do not think it is gear whine as you can sit in neutral, without the car moving and still hear the whine as the RPM surpass 1950 RPM - it sounds like it could be a pulley or tensioner. I have had the car evaluated by Porsche AND two independent shops. 2 of 3 suggest it is normal.....but I don't care if it is normal, I want to fix it. I know the previous 981 GT4 has an AOS recall, and I appreciate that this might also be related to the AOS. Does anyone have a recording they can post of the before and after?...I want to compare it with my vehicle. Can anyone else confirm that the new part number listed above does reduce that sound in more than the single case cited? I have already removed the sound symposer and added dynamat and mass-loaded vinyl, but the whine persists. Finally, if the 4.0L is a variant of the current 911 (992) motor, why doesn't the sound exist on that vehicle?
THANKS!
I am glad I am not the only person who thinks the rev-correlated whine is a substantial distraction from the driving experience of the GT4. I have been looking all over forums to find a complete story -- I have had my car since new, and do not recall hearing the sound during break-in period. However, over the past year, it has gotten quite annoying. I do know that the sound at least exists on another 718 GT4 I have driven. I do not think it is gear whine as you can sit in neutral, without the car moving and still hear the whine as the RPM surpass 1950 RPM - it sounds like it could be a pulley or tensioner. I have had the car evaluated by Porsche AND two independent shops. 2 of 3 suggest it is normal.....but I don't care if it is normal, I want to fix it. I know the previous 981 GT4 has an AOS recall, and I appreciate that this might also be related to the AOS. Does anyone have a recording they can post of the before and after?...I want to compare it with my vehicle. Can anyone else confirm that the new part number listed above does reduce that sound in more than the single case cited? I have already removed the sound symposer and added dynamat and mass-loaded vinyl, but the whine persists. Finally, if the 4.0L is a variant of the current 911 (992) motor, why doesn't the sound exist on that vehicle?
THANKS!
01-07-2024, 07:16 AM
#89
Drifting
Thread Starter
I have commented on this thread previously. Have a 981 GT4. The whine drove me crazy once I heard it I couldn’t unhear it. Got the updated AOS part following the advice here. Not a lick of difference. Save your cash. Fast forward 6 months I’m just used to it now. Thought I’d share my thoughts so you don’t find out the hard way. No before after sound I’m afraid.
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zhouto (07-28-2024)