996 C2 poor brake performance?

Hi all, I've been having some issues with the brakes on my 2003 996 Targa - purchased a bit over two years ago with brakes recently done (at that time, so it's due for a fluid change). The car hasn't been tracked or driven excessively and there's no noise coming from the brakes (except today, as below). I've always had to put in fair effort to brake, but it was possible to get the ABS to kick in. Over the last couple of months the vehicle has been mostly parked - but I recently moved and have had it out for the last couple of days doing some driving in hills... Today, I was driving through some twisty roads and the car in front hit its brakes hard. I had to stop quite suddenly and despite *really* stomping the pedal, I was actually concerned that I wasn't going to be able to stop in time (there was ample stopping distance given the speed invovled). After this happened, I noticed two things: 1) some noise upon braking and some very mild shimmy from front right wheel, and 2) a strip of 'polished' metal near the outer edge/rim of the front left/right and rear right rotors. I'm far from a brake expert and don't have a micrometer at the moment to measure the rotors thickness (but will get one). The car is already scheduled for maintenance and I'm sure the right front rotor is done (although after cool down I didn't notice the shimmy on a short test drive). The rotors otherwise look ok, no dash lights, etc. The fluid level is fine (checked) but does need to be changed - could this just be due to a fluid issue? Also, any benefit to braided hoses? (since the car will be up in the near future with the wheels off)

Thanks 911C, this is only my opinion, but if you can afford it, I would start will a clean slate of parts. Fluid, Rotors, Pads. The 996 stock braking system is the best on any car that I have owned, and I lightly tracked the car for 2 years with the brakes. Once refreshed you should have not problems. I personally would not do the braided hoses since it is a street car (unless the hoses look worn or are leaking). If you do your own work, look at RockAuto for Pagid or Sebro rotors. Textar or OEM pads and decent fluid (there are many recommendations in the forum). Please report back on your decision.

Are there any other 996 owners you live close to that would be willing to drive your car for comparison? I�ve noticed that seemingly identical vehicles have different brake feel. My Mini Cooper was stiff (brake pedal) compared to a different one I�ve driven. My wife�s Audi SUV is much softer than a different one. I�d make sure to compare before you throw parts at it. Could be a lot of money and very little change. The pedal effort is directly related to the amount of vacuum available and that vacuum applied to the booster. From there, it�s going to be pads and rotor matchup. If the wrong pads were used, it could have a negative effect. If someone put track pads on, it could have the effect you mentioned.

OP. - My 2c...look at all the hardware for differences/defects, check fluid condition and bleed all 4 corners. Go from there.

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You mentioned the easiest solution in your 1st line but I guess you were unable to stop.

Thanks Mike and Rachet1025, Alas, nobody I know of close by that has a 996, but this is certainly out of the ordinary (e.g., I had a rental Toyota RAV4 a few weeks ago that would stop in a shorter distance than my 996 at the moment). I'll start with the fluid as suggested and go from there. Any easy way to check the vacuum (assume not argh)? The pedal engages and is not spongy. I'll snap a photo of the rotors tomorrow just for reference. J.

Take the opportunity to change fluid but it won't be the cause. I suspect your pads arr are of the low-dust variety that require greater pedal effort than regular porsche pads as their coefficient of friction is lower than regular pads'. The shimmy and noise after that stop are probably due to pad deposits on the disks. Did ABS kick in? Another possibility could be, as already stated above the level of vacuum to the brake booster or the booster itself. An indication is given by this test: 1.Hard pedal feel or regular pedal feel after the car has sat for 8h or so? 2. With the car sat for 8h and engine off, how often can you depress and release the prayer pedal before it becomes much harder to depress? Have a look at the master cilinder as well. Perhaps somebody put a 25.4mm or bigger one instead of the stock 24.6mm one. The diameter is cast in the part itself. Only a strip of polished metal.on the disk (post a picture!) seem to indicate that the pad surface doesn't fully contact the disk. This can happen when pads partially worn on a very worn drilled disk (different from slotted...) the drilled disks develop a wavy wear pattern (radially i.e. from the center to the outer edge you'd feel.the lows and highs) and so do the pads. Changing only the disks for new ones while keeping the pads results in a reduced contact patch between the flat disk and wavy pad.

Sounds more like your point 2 is the problem if the pads aren�t making full contact with the rotor. You can try re-bedding them but sounds like time for new pads and rotors anyway.

Hi all - thanks much for the assistance. Sorry it took me some time to get the photo - previously the discs did not look like this, until after the mountain run when I was hard on the brakes.The surface may be uneven (hard to say by touch). With the engine off for 8 hrs., I can push the pedal down maybe by 1" two to three times tops before it becomes rock solid. Based on the rotor appearance, must be 2. as @hardtailer and @jayzbird suggest. See outer edge of disc...

New rotor time. Hard to think what would cause that unless the pads are so gone you have metal on metal. Or some tough little rock got in there, but you would have heard it scraping. Anyways, it�s an easy diy. It would be interesting to see a pic of the pad once you get it out.

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Brake booster and vacuum lines to it are ok if you can press 3x before pedal going solid. Can you feel a ridge or step up/down when you pull your fingernail across the surface? It'd be interesting to know whether the shiny area lies deeper within the disk than the matte greyish surface Replace pads and disks and make sure both inside and outside pistons move freely inside the front calipers. Does the front disk on the other side look like this too?

It's difficult to discern any ridge when running my nail up and down the rotor (the surface does feel different, but there's no obvious indent). Rotor on the other side looks similar but not as much of a polished band. Anyhow, stepped up and ordered a full kit for all four corners (rotors, pads, etc.) - I'll take some photos of the pads and the rotors once everything is apart and report back here. Thanks all!

Following up with news and questions for folks: I pulled the pads on the front right side - worn but not totally gone (1/4" left). However, two things: 1. I cannot, for the life of me, get the pistons in the calipers to retract - they are absolutely, fully frozen. I ruined a cheap pad spreader trying, without any motion at all - this in part explains why it was very difficult to pull the old pads out. I can only guess that, in fact, part of the poor braking performance has simply been due to the pistons being fully corroded. I'm amazed - the seals look good and the undercarriage is in great shape. But I've only owned the vehicle for two years (and did use much in 2020). 2. Given the above, I'll need to replace the calipers I think - re: bleeding the system, I've been told that because my car has PSM, I can't fully bleed myself? (need to move the PSM values) Anybody have comments on this? I unfortunately don't have the space or expertise to attempt to rebuild the calipers (nor am I sure it would be worth it) - does anyone have a suggestion for (red) rebuilt calipers? Thanks all.

Have determined by a shop or the like whether your calipers can be rebuilt. If you clamp the brake hoses shut before removing the calipers then only a normal brake bleed procedure is necessary. Replacing the psm module or pre-pump now that would require piwis or Durametric in order to bleed the system.

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I've had similar experiences w/my 2000 C4 Cab as detailed in other threads. EVERYTHING in my car's brake system has been changed -- Brembo rotors, Akebono pads, StopTech S/S brake lines and a new OEM master cylinder -- and the brakes were bled MULITPLE TIMES by my Indy and by the dealer who each said everything is FINE!!! Well, it's NOT fine IMO when compared to my 4 other cars (a C7, 335i, MR2 and ML350) and my F250 which all stop "better" than my 996. So, IMO, the brakes just suck. A couple of other things "could" be done that "might" make the brakes perform better but I'm tired of trying to "fix" the problem after already spending about $2k on it. Those "other" things include entirely rebuilding the calipers and switching out the pads but I'm not going to do that because I'm DONE trying to "fix" the problem to my satisfaction. The car stops but just not as quickly as I'd prefer. So, I just allow for more time to stop and (while I never tailgate anyway) I make sure that I have at least 3 secs (or more) time distance between me and any cars in front of me in case they stop unexpectedly. Hope you can fix the problem to your satisfaction OP but I have never (or at least not yet) been able to do so.

...what sort of tyres are on your 996? Can you get the ABS to kick in? Brake booster working as it should ( brake pedal going stiff with engine off after say 3 full force brake actuations or after the first one/perhaps even immediately)? Have you had the chance to drive another 996? Rebuilding the calipers is fairly easy and a set of seals is not too expensive. The good thing is you can tell by any corrosion you see inside the bores or on the pistons that you'll benefit from the rebuild. The calipers live in a harsh environment much more so than the MC you had replaced.

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Im guessing the 2-yr brake fluid flush was not done routinely on this car; otherwise, that�s just bad luck or unfortunate circumstance. But stuck calipers would certainly explain your issue, no doubt.

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I've seen comments like this about some cars here, and I wonder whether something else is going on, like a brake booster issue. My 2000 C2 stops better than any other car I've had. I have supreme confidence that if I make a mistake the brakes will bail me out. So like I said, I wonder if there's something not at the wheel causing these issues, which I have heard more than once. Does anyone know if there's a brake booster sensor like on other cars that we may have replace? Hope you get it figured out because I can't imagine driving a car with brakes you don't like is any fun.

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Don't know but I had the car at my local dealer to check the brakes (while doing some other more important work) and the service manager (who ended up handling the matter) told me that there was NOTHING wrong w/the brakes in his opinion. I'd think that if the brake booster was even a question that he would have brought it up but he didn't. Don't think he'd avoid bringing it up if it was a consideration. No skin off his nose and more $ for the shop if such a repair/replacement was required. Told me that the thought the brakes "braked hard" and were fine. Didn't bother trying to dispute his assessment despite NOT sharing his opinion either b4 or after they inspected the brakes.

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Yeah, I get it. The dealer is supposed to be the authority on these cars, but I don't know that they are always the best place to take our cars. My advice on your next steps would be first to identify if you have an issue. I know this is tough, but maybe find someone else with a 996 who is happy with their brakes and see if you feel any difference. Long shot I know, but I'd make sure what your feeling is right before you spend any more money. Then, if the second car's brakes are better than yours, find an indy that understands your issue. Everything at the wheels (and beyond) has been changed and you still don't like the brakes. I'd call around and stop on the guy who has some suggestions other than replacing everything at the wheel again. Sorry, not much to offer other than in my opinion your brakes shouldn't let you down. Good luck!

Hi everyone! Just wanted to thank the group on this thread for all the help. It turned out to be quite an odyssey to fix the brakes on my 996. After finally getting everything apart, I discovered that the previous owner (I think) had done some shady painting of the calipers (from black to red), probably without being at all careful. And also almost certainly had not kept up the maintenance. I ended up getting some used calipers in very good shape for the front, and buying new ones for the rear (argh), then changing out pads and rotors plus hardware and some other parts. After a couple of bleeding sessions and a lot of cursing, the brakes are now in very good shape and the car stops the way it's supposed to (hooray). I also have some new tools 😀. Here's a picture of the back all cleaned up and ready to roll.

Wow, that looks and performs much better! Great job. Are those the front calipers in your picture? They look new.

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Ah, that's right rear (new caliper) - pricey but sure does drive (and stop, whew) better!

Good to hear you found the cause. Show us a pic of the area of the painted calipers where the pads go please.