Really LOUD startup rattle
06-22-2005, 04:57 PM
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Really LOUD startup rattle
Guys,
I have a rattle emanating from directly under the car around the middle...not from the actual engine area. It's not the typical noises you hear from Porsches upon startup and it doesn't sound like a drivetrain or valve lash issue. This one is loud and brief when starting; it lasts for no more than one second and I can actually feel the vibration. It only happens when the car is cold...after sitting overnight. Never again for the rest of the day. This really got bad after a recent track day. Got under the car with a mechaniic friend and we could not pinpoint the issue. Could this be related to the "vibration" or rattle I hear when driving the car at around 2000 rpm to 2500 rpm? Would love to hear your opinions before I take it to the dealer techs. Thanks in advance.
I have a rattle emanating from directly under the car around the middle...not from the actual engine area. It's not the typical noises you hear from Porsches upon startup and it doesn't sound like a drivetrain or valve lash issue. This one is loud and brief when starting; it lasts for no more than one second and I can actually feel the vibration. It only happens when the car is cold...after sitting overnight. Never again for the rest of the day. This really got bad after a recent track day. Got under the car with a mechaniic friend and we could not pinpoint the issue. Could this be related to the "vibration" or rattle I hear when driving the car at around 2000 rpm to 2500 rpm? Would love to hear your opinions before I take it to the dealer techs. Thanks in advance.
06-22-2005, 05:32 PM
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Perhaps a loose heat shield inside the rear bumper cover. Also, check your exhaust... there may be something loose like a tip or cat clamp. Maybe one of your cats is toast.
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06-23-2005, 01:51 AM
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Its either the O2 pump bracket that has come loose and is vibrating and the sound is resonating thru the tub. The car has no insulation, so just because you think its coming from the middle of the car, does not mean that it is orginating from the middle of the car.
It could also just be the oil trying to get to the pump from the pan.
I always let the car warm up for at least 5 mins before drive off.
You have to remember that PAG/PNA suggests driving off immediatly and vary RPM's, but thats for emission issues. Race cars are all warmed up before being driven and I would do the same with all High compression engines.
I do it with the Ducati, so why not the GT3.
It could also just be the oil trying to get to the pump from the pan.
I always let the car warm up for at least 5 mins before drive off.
You have to remember that PAG/PNA suggests driving off immediatly and vary RPM's, but thats for emission issues. Race cars are all warmed up before being driven and I would do the same with all High compression engines.
I do it with the Ducati, so why not the GT3.
06-23-2005, 02:28 PM
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Originally Posted by cosmos
I always let the car warm up for at least 5 mins before drive off.
You have to remember that PAG/PNA suggests driving off immediatly and vary RPM's, but thats for emission issues. Race cars are all warmed up before being driven and I would do the same with all High compression engines.
I do it with the Ducati, so why not the GT3.
You have to remember that PAG/PNA suggests driving off immediatly and vary RPM's, but thats for emission issues. Race cars are all warmed up before being driven and I would do the same with all High compression engines.
I do it with the Ducati, so why not the GT3.
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06-24-2005, 02:18 PM
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Really LOUD startup rattle - [EDIT] Really BAD news
Guys,
The Bad News
I have just been informed that I need a new engine. Yep, you heard it right, a new engine. The service tech, a really nice, low-key, knowledgeable "kid" diagnosed the problem as an intermediate shaft gear that is "pressed on" to the shaft and has come loose. He said he knew what it was as soon as he started the car.
Damnit, I knew something was up when the tech disappeared for a long while shortly after putting the car on the lift.
The Good News (I think)
The disappearance was due to the tech and the service manager being on the phone with the district manager who has, as far as they tell me, already authorized a new engine. The guys told me that Porsche does not want them touching the shaft or pullling it apart; they want the engine pulled out, crated, and sent back to Germany. I will retain my exhaust and cats...everything else will be new.
The guys told me that they have recently seen "several" of these failures, albeit on 996TTs which, they were quick to point out, use the same block as the GT3 (I knew this). I guess I haven't been paying enough attention to the 996 Turbo board; I don't recall seeing anything on this issue over there.
It's not in my nature to now start slamming Porsche or lamenting my bad fortune (at least since I have gotten older and wiser). I am focused on taking care of the problem as analytically as possible. I have already stated my concern that the engine has to be knew...not rebuilt. Their answer is that this should not be a problem given that there aren't many of these cars around. In their words, the engine will be new. Is this a valid concern? Does it even really matter? Are there spare 996 GT3 engines just lying around? Will numbers match? On the positive side, I guess I'll basically have a new car again.
Sorry for the length of this post. Any advice on how to cover all the bases and ensure a positive outcome is appreciated. So far my interactions with the dealer service people were very positive. Funny, this is my first visit to this particular dealer as our local Porsche dealer is now basically out of the business. What a way to start a relationship with a new service department!
The Bad News
I have just been informed that I need a new engine. Yep, you heard it right, a new engine. The service tech, a really nice, low-key, knowledgeable "kid" diagnosed the problem as an intermediate shaft gear that is "pressed on" to the shaft and has come loose. He said he knew what it was as soon as he started the car.
Damnit, I knew something was up when the tech disappeared for a long while shortly after putting the car on the lift.
The Good News (I think)
The disappearance was due to the tech and the service manager being on the phone with the district manager who has, as far as they tell me, already authorized a new engine. The guys told me that Porsche does not want them touching the shaft or pullling it apart; they want the engine pulled out, crated, and sent back to Germany. I will retain my exhaust and cats...everything else will be new.
The guys told me that they have recently seen "several" of these failures, albeit on 996TTs which, they were quick to point out, use the same block as the GT3 (I knew this). I guess I haven't been paying enough attention to the 996 Turbo board; I don't recall seeing anything on this issue over there.
It's not in my nature to now start slamming Porsche or lamenting my bad fortune (at least since I have gotten older and wiser). I am focused on taking care of the problem as analytically as possible. I have already stated my concern that the engine has to be knew...not rebuilt. Their answer is that this should not be a problem given that there aren't many of these cars around. In their words, the engine will be new. Is this a valid concern? Does it even really matter? Are there spare 996 GT3 engines just lying around? Will numbers match? On the positive side, I guess I'll basically have a new car again.
Sorry for the length of this post. Any advice on how to cover all the bases and ensure a positive outcome is appreciated. So far my interactions with the dealer service people were very positive. Funny, this is my first visit to this particular dealer as our local Porsche dealer is now basically out of the business. What a way to start a relationship with a new service department!
