soft initial brake pedal feel and long travel
Since I've bought my Panamera about two years ago I've always noticed that the brake pedal seems to have a long travel and feels quite soft before it really does anything. You get use to it and it does stop when needed but it's not quite up to what I believe a true sports car brake system should feel like. I had the brake system bled by the dealer as a normal 2 year or less maintenance but it still doesn't seem to feel quite right. Anyone else experience this? We're talking about a car here with less than 25K miles so brake pads and rotors should be fine. I'm definitely going to have the dealer look at it again when they perform the latest recall on the cooling pump SVR issue when parts come in.
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Tom
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Have you driven another Panamera to compare? I know some non-Porsche luxury cruisers have soft inputs all around. I wouldn't expect that with Porsche where even the SUV's feel pretty sharp, but might be worth comparing just to rule out the possibility... ?
No I haven't but given the image and often well deserved reputation for such sharp handling, braking is a very strong part of that equation. I wouldn't expect them to shortcut that in one model vs. another. I just had my 2012 G37 Infiniti's brakes bled/flushed and that's what they be like in the Porsche. No doubt about what to expect.
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dr bob
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Does the pedal "pump up" with multiple quick stabs at it? I don't have a Panamera but do have its sort-of predecessor. I trust that the brake bleed included some pad inspection, so for now let's rule that out. On my more 'period' car, the pedal feel is extremely sensitive to any air in the system, and to the pad material. The air in the system problem is pretty easily identified with the pedal able to be pumped up. Twice I've managed to accidentally get air in the system during fluid changes, and the only real solution was "vacuum bleeding" the system similar to the way it was filled at the factory. The lines to the MC get capped, and a hard vacuum is pulled at a caliper (front or rear). The bleeder valves get some silicone grease on the threads to eliminate leaks. Then fluid gets drawn in from the opposite side bleeder after purging the connecting hose of any air. Close everything up, and repeat at the other end of the car.
Once completed, the MC gets an on-car "bench bleed" with return pipes fitted to each port. Then with an assistant or a stick holding the pedal part way down, a return pipe is removed, the cap removed from the mating pipe, and the pipe is connected. On my car, there's also a bleeder at the end of the front section of the master cylinder, essential since the MC is slightly nose-up. That gets bled during the on-car "bench bleed" process but with just a short section of hose instead of the hard return pipe.
It seems like only some specialty race-prep shops are able or willing to perform this level of service. It's the method required for cars with silicone (DOT-5) fluid. If you can't get all the air out with the conventional pedal or pressure bleed procedures, a full vacuum fill like this may be the solution.
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In my 928, the ABS unit is the "high spot" in the system, so any air introduced from the MC end tends to hide out there. In additions there is a high spot between the rear brake calipers that can hold air bubbles captive. I can actuate the ABS unit to pump fluid through, but that only purges half of the unit. Pulling all the air and old fluid out means that new fluid will be drawn back to completely fill every part of the system. In a couple clinic cars the caliper pistons leaked air under vacuum, requiring a modified procedure that cleared the calipers of air separately, and refilled them with a pressure bleeder. So there are some things to keep track of if you decide that vacuum bleeding is needed. In the end though, the difference in pedal feel is pretty amazing.
Once completed, the MC gets an on-car "bench bleed" with return pipes fitted to each port. Then with an assistant or a stick holding the pedal part way down, a return pipe is removed, the cap removed from the mating pipe, and the pipe is connected. On my car, there's also a bleeder at the end of the front section of the master cylinder, essential since the MC is slightly nose-up. That gets bled during the on-car "bench bleed" process but with just a short section of hose instead of the hard return pipe.
It seems like only some specialty race-prep shops are able or willing to perform this level of service. It's the method required for cars with silicone (DOT-5) fluid. If you can't get all the air out with the conventional pedal or pressure bleed procedures, a full vacuum fill like this may be the solution.
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In my 928, the ABS unit is the "high spot" in the system, so any air introduced from the MC end tends to hide out there. In additions there is a high spot between the rear brake calipers that can hold air bubbles captive. I can actuate the ABS unit to pump fluid through, but that only purges half of the unit. Pulling all the air and old fluid out means that new fluid will be drawn back to completely fill every part of the system. In a couple clinic cars the caliper pistons leaked air under vacuum, requiring a modified procedure that cleared the calipers of air separately, and refilled them with a pressure bleeder. So there are some things to keep track of if you decide that vacuum bleeding is needed. In the end though, the difference in pedal feel is pretty amazing.
dr bob
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1989 928 S4, black with cashmere/black inside
SoCal 928 Group Cofounder
928 Owner's Club Charter Member
Bend Yacht Club Commodore Emeritus
Free Advice and Commentary. Use At Your Own Risk!
I've been doing brake bleeds in my cars since 1966 using the old fashion pump the brakes with a helper (still used in SCCA racing groups in paddock) to a more sophisticated vacuum setup working off each caliper and making sure the master cylinder is always topped off with no air in it. My last 2 cars, before the Porsche, was a 91 NSX and a 2012 Infiniti G37S coupe. All of these use a similar fixed caliper setup and when done only the Porsche never feels rock hard or solid under normal use when needed. Don't get me wrong the Porsche will stop when it has to but it just doesn't seem to give much pedal feel while doing it. It just feels spongy until the very end of the travel. The dealer has done the last 2 brake flushings for me since I'm starting to feel my age a little and don't like doing it myself anymore while on my knees. Since this is my first Porsche, I have no real comparison from any other car out there. Dealers today don't want to bother to allow you to use one of their loaners/used version of this car as a comparison check. Thanks again.
Al
Al
We had 2018 Panamera E-Hybrid and the brakes were great for such a big vehicle. The E-Hybrid does have a different feel in braking (regen) but definitely not spongy at all.
I've also driven the Panamera GTS in braking exercises at the Porsche Barber school and the brakes bite quick and hard. Something sounds wrong in what you describe.
Sorry can't be of any technical help but hope you can get the issue resolved.
I've also driven the Panamera GTS in braking exercises at the Porsche Barber school and the brakes bite quick and hard. Something sounds wrong in what you describe.
Sorry can't be of any technical help but hope you can get the issue resolved.
I have a 2016 Macan S with 116K miles and a 2010 Panamera 4 S with 250 K miles and brake feel is definitely different and always has been. As described, the Panamera is softer with slightly longer travel, but will nonetheless stop on a dime. The Macan ( to me drives like a 911 SUV) brakes are more sensitive and firm and get the job done as well. I just consider them two different driving styles for the Porsche enthusiast. And I love driving them both; such awesome driving machines. They are unique within the Porsche family. I have had: 1993 911 4S ( my very first), 1996 Twin Turbo, 2006 Twin Turbo, before settling on my current vehicles. My point is just that they will all have a different style of driving in all aspects.
Finally got the dealer to allow me to drive a newer ON-LOT car for comparison and I'm sorry to say that the Panamera 4 base model even with those huge brakes on both of these cars acted very similar. The test car only had 5K miles on it while mine has about 26K miles. However mine has always felt this way since I got it. I just have a feeling that Porsche has made a decision to make the Panamera a slightly softer version of their sportier models. It's their luxury 4 door vehicle model and this is one area where it shows it. Again I'm only comparing it to cars which I know do the brake pedal feel better. Not going to trade it because it does everything I need a luxury wagon to do and then some. 