I will be getting new pads+rotors with a front passenger caliper replaced in about a week, but have a quick question.

For the past few months I've been driving with a wierd brake pedal. I want to describe as "spongy" but I would say that its more than that. Sometimes especially after leaving the highway I press on the pedal and it feels like there is a rather large "bubble" in the brake pedal and it takes about 1/2 second to "push that bubble" and get the brakes to grab. After that the car stops fine for some time. The pedal does not feel hard or anything, it just needs that 1/2 second to grab. Is this just air in the lines and the combination of needing a new caliper with pads+rotors or does my master cylinder need replacing too (hope not..)

I know it sounds a little silly but any help would be appreciated.

TY

PS. The pedal does not go to the floor when stopping or at traffic lights, nor does it get hard after a while.

If the right front caliper is sticking (reason for replacement) that will generate a lot of heat and may have boiled your brake fluid. A small amount of air in the brake line will produce the sensation you are having.
While your brakes are being worked on, have them flush all of the fluid with new.
Also check the brake lines for cracking. If they are, replace them with braided steel lines, only $20 each from FCPGroton. A worthwhile option.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)