feels like the brakes are bleeding down.

[PT Sportwagon]

I am having a weird problem with my sportwagon. When I am at a light the brake pedal acts like it is being bled, it will be firm then drop, like the bleeder was opened. I am not loosing any fluid. the car seems to stop fine 99.9% of the time. Could it just be old fluid or water in the system? needing the system slushed.

Tim

[Apogee]

It could be several things, including a bad master cylinder, but let me ask you this first. Does your car have a power booster? What sort of vacuum does your engine generate at idle? What cam are you running? It's possible that your vacuum is fluctuating with rpm and load such that you mostly notice it at a stop.

I'd start by inspecting/replacing the vacuum check valve in the booster and then the master cylinder. If you can apply steady, firm pressure to the brake pedal and the pedal sinks slowly over time, then you've got either a hydraulic leak somewhere or a bad master cylinder.

HTH,
Tobin
KORE3

[PT Sportwagon]

I found it was the master. I am running a stock cam ( for now) but I replaced the master and after a adjustment and bleeding. it works great.

Thanks

Tim