tstafford

Yep. The thing that's annoyed me is the down time. I thought I'd be fine with this process but I didn't count on wanting to drive the car so much. Wasn't expecting it to be so much fun. I miss it when it's in the shop - which is a lot right now (probably close to half the time I've owned it thanks in large part to the widespread mechanic shortage).

TheOtherEric

Did your shop have any explanation as to how a mc failure caused the warning light? I’m just curious to know how that happens, since the mc is a purely mechanical device. Always smart to approach these things with an ounce of skepticism.

It’s a pretty simple fix so shouldn’t be too expensive.

tstafford

No. I'm going to chat with them later this AM after they get some more time w/ the car. We'll see.

Also - folks were right about the "leak". Condensation from A/C, unrelated to brake issues.

pp000830

If this is in reply to the OP, I respectfully disagree.

• My understanding and limited experience is that the ABS booster pump only comes into play when the sensors trigger it, outside of this it is a passive device. If inoperable it simply doesn't kick in during triggering events and the braking system acts like a non-ABS system
• When one of the two sections on the master cylinder fails, or gets air in it, braking becomes very hard as the remaining section takes over the work. This is a fail-safe design I believe has been required by law for many years.
• If the problem was a fluid leak, even a small one, the brakes would just fail with no stopping power and so very unlikly
• If the problem is the brake fluid level got too low and the system sucked some air into the system that could be the issue. I would bleed the brakes first to see if that resolves the issue the if not investigate the master cylinder.

Andy

tstafford

That's super helpful and makes a lot of sense.

FWIW - While I am absolutely not a mechanic, I do know a fair amount about driving. There is no way anything I've done with the car would have triggered the ABS system in the last few weeks (and certainly not yesterday when I noticed the issue). So by your comments Andy it should have remained "passive". My indy isn't the most experienced with air cooled Porsche but they always get things right in the end. I trust them and believe them when they say they believe it's the master cylinder but want more time to finalize their diagnosis.

pp000830

The only other components involved are the push rod mechanism under the brake peddle and the brake booster. Both of these areas/components have proven to be extremely robust on our cars altho a malfunction of either can dramatically increase required peddle force.

TheOtherEric

That would also explain the warning light (fluid level sensor in the brake fluid reservoir). So my guess is low fluid, and the next question is why did the fluid level suddenly drop.

Endoman

It's not rocket science, the leak is probablty from the vacuum servo, hence heavy pedal. Warning light = low fluid level. ABS not related , it's triggered by the wheel sensors which also give a warning light if one fails.

TRIPLEBLK1

Check the hydraulic booster!

tstafford

That's the current area of focus. So I hope you (and my indy) are on to something.

BTW - Thanks for all the advice. I appreciate it. Hope everyone has a good holiday weekend.

Going to spend some of mine trying to install my Waldemars and also fresh speakers from Einmalig. If the car isn't driveable it may as well look and sound great.