Took an alternate route to work this morning, one that has a very steep, long hill down about 2.5 to 3 miles in length, from about 1000 ft to sea level.

I used the brakes a lot, and then they began to feel spongy, like I had to pump them for them to work.

After some driving on level ground, the brakes appeared to work normally again.

I looked for some leaks, but did not see any around the grommets or around the reservoir.

Is this a master cylinder failure? Or air in the lines or ????

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1991 300E 124.030 103.983KE 722358 03 412178
207K

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