P.Viby

Short update - Porsche can't provide any new spare part, but have offered 2 new discs. (Thank god that I have the Porsche approved assurance) 

Hi guys,

Seen on the picture there is a bolt and spring missing from the disc. Any idea where I will be able to buy one of these? 

Porsche says there is no separate part number for this and might suggest a hole new disc?

Any help would be highly appreciated.

I am not sure about the Turbo but I seem to remember that for the Turbo S they used another metal for the cylinders, it is not aluminum. 

I once had mine replaced - all worked fine. Would be VERY strange if you get 6 bad brand new PCM units in a row from Porsche. 

I think they each time transfer some settings from the old PCM unit to the new they install. Maybe these data are corrupt and they then fail the new unit. Perhaps you can ask them to setup the PCM unit manually.

I was in the same dilemma as you when I bought my car. The Turbo  or Turbo S are fairly cheep due to the big cut they take compared to the GTS. But as I was told by 3 different Porsche dealers. If you come from a 911 and want some of the same driving qualities go with the GTS. I did and bought a GTS. Absolutely fantastic car with GREAT sound.

The GTS is setup more like a sportscar where the Turbo is more like a limousine and great in that perspective.

Reading these types of topics are really scaring me off from using ceramic rotors on the track, so if I can convert for ~$2k, I would rather go that method and keep the value in my ceramic set.

 

http://rennlist.com/forums/991-gt3-and-rs/836922-pccb-wear-on-track.html

I see your point - but again, I would not be afraid doing it, unless we are talking some kind of endurance race or a lot of track days for a long time.

Remember to get them warm, before slamming the brakes. The highest tear on PCCB discs are actually when they are cold. Remember to go with fairly new pads.

Porsche has always been known for making super and long lasting brakes, a few track days is not a problem for these cars.

Cost of replacement rotors if I take the car to any high performance driving events.

Unless you have a plan showing up in some kind of endurance race with the car, I still don't see the point. The PCCB brakes can easily handle some races on a track now and then without tearing them down significantly. The discs are made to last very long, that is the hole idea more or less with the PCCB brakes and the price for pads are the same.

But as Loren said - most likely you can do it.

Just curious- why do you wanna change from PCCB to normal steel brakes ?

There is a TSB out concerning faulty ground wiring. This can cause all kinds of warnings also. But as JFP says, start checking the alternator output. Look for an output of 14.0 volts or higher. Apply load from, lights and seat heating, etc. and make sure voltage does not drop down to much. You don't wanna see anything below 13.2 volt I would say.

I would hook it up next to the engine vacuum pump. So it is kind of parallel system to the engines system.

Welcome to the forum. As already said. This does not really sound like a "DIY" job.

What sounds strange is that even with the engine off you say it starts to leak from the hole between engine and transmission.

I would agree with the OP. The first time I drove the car I was disappointed of the brake feel. I had to push really hard to get some deceleration. I changed the brakes and I had the case that the inside of all 4 rotors was corroded. So I exchanged them and did a brake flush. It's somewhat better now but still not what I was hoping for. My Infiniti and Mercedes have better brakes with more bite. It might be an issue of having better feel when braking. I could imagine that the Porsche brakes are better on the race track but just daily driving they are not thrilling.

I strongly doubt that your Infiniti or Mercedes have better brakes compared to the 996. Be course you feel that you need to push the pedal harder for it to brake is just becourse the brake amplifier is adjusted in a different way on the 996. If you wanna compare brake systems with each other, take the cars on a track and see how they handle when they get pushed to the limit.

Check rotors and pads. Use the Porsche OEM parts. Porsche is known for making some of the best brake systems. Worn out rotors and pads could give you the feeling of brake pressure you describe. See if you can get a look at the rotors from behind. It can be heavily corroded on one side even it looks good on the other.

Let the shop check your altenator and if it charges correct. Also a faulty alternator can drain the battery when the car is turned off.

And in the end you actually buy a Varta battery. Quite sure they produce OEM batteries for Porsche.

PDK overheat could maybe be the problem your experience with the transmission.

Regarding the brake problems. First I would check if your brake fluid is good enough. Check level, but more important check if boiling temperature is within limits. Unless the specific track is very brake demanding I would not suspect brake fading from overheated brake rotors and pads. But of course old pagid pads and worn out rotors could give you the symptoms you describe also.

Not the best idea if you ask me. It will cost you a lot of money and only if you are lucky the value remain the same. It will for sure never pay back.

Stay happy with the S or get a GTS :-)

This starts to sound like you have a faulty battery. When it won't start - try to jump start it.

I would not be afraid to wait for sensors to cut though. It is a good and simple system and you have backup from other sensors. Plus using steel discs it won't damage them that much if running metal to metal. In that case you will hear it right away.

I have PCCB on my PGTS. There It hurts if going metal to discs.

Best thing always is to take the battery out and charge it somewhere warm for 24 hours to make sure it is fully charged.

I have a 6 channel HAES M490 Amp I don't use. PM me a let us see what we can find out.

It is actually very easy to access and expect. Check vacuum lines and the vacuum valve. All can be done in less than 1 hour.

I don't know if lifting the car up and run it for a short while can damage it so much. But then try to put it on those test bench used for measuring HP. That for sure does not damage it as long as you use one made for 4WD.

It will give you a much better chance to locate the noise or at least rule out some sources.

Hi

The noise doesn't happen at any certain RPM range, it's a speed range. I can listen to the noise, during the speed range, and downshift from 7th to 6th to 5th and still hear the noise. I can only stop the noise by moving outside of the two speed ranges or changing gears from Drive to Neutral.

Thank you for your replies.

John

Try putting the car om a lift. Put it in gear and let it run up to the RPM where you normally hear the noise. Then you can rule out the wind theory if it is still there. Also doing this you have a chance to go around the car and listen to where the noise comes from.

Funny enough this tip is what you do a Porsche 968 when checking it for pinion bearing problems.