Was wondering what would cause my brakes in my 90 camaro to be xtra touchy when it's cold out and cars not warmed up to above 150ish??This has only started since the cold weather has set in.When ya lay on the brakes even a little bit no matter how easy when she's not up around normal temps for the first 3 or 5 times they seem to act like ya stomp on them.Like yer tryin ta stop b4 ya run over a kid.All tires squeeling and such.Basicly they lock up.Once they have gotten this out of their system they behave all day.
Any ideas??Fluid levels fine.Looks like normal blk/brn color like old fluid does.Have thought of bleeding lines till it's almost clear again but rather wait till summer for this.No garage and cold ground with gravel driveway and puddles tend to make this prospect suck bigtime.

 

 

Hmmn hadn't thought of that but possiable.Altho dunno why the RO is the only one that happens to.

 

I had a ford F150 that behaved exactly as you are decribing.

First thing in the morning, if a fly landed on the pedal it would put you throught the windshield.

My solution was to back it our of the drive way dragging the brakes before going on the public road.

I never figured out the problem. Just a way around it.

I don't understand the moisture thing. Seems this would make them not want to stop until it was burned off.

 

Well odd thing was this mornin and last night as I sat there for a sec or three waiting for the oil ta circulate thru the engine.(warming up the car)I pumped the brakes a few times ,and ya could hear the rpm's rise and fall with the pumps.(rise on depress and fall on relaese).Never remember ANY of my other vehicles chev ford or olds doing that b4.Wonder if that check valve to the master cyl might be goin bad?Oh and when I pulled off both times brakes behaved fine.NO issues at all.

 

bump??

 

When your brake pads absorb moisture, they swell. As your pads swell, well the distance between your pads and rotors is reduced considerably. This is why your brakes are extremely touchy on cold days.(think how moisture condenses overnight to form dew and fog in the morning)

The normal behaviour is to have some slight slack inbetween the pad and rotor, which gives a more graduated feel in the pedal.

I'm not sure why your rpm's would fluctuate like that in the morning, but I don't think it is related.

SDIF was just basically heating up his brakes as he left his drive, and that drove(no pun intended) the moisture out of the pads.

 

Ok I could see that if it happens to some of the other cars I have/have had over the years.But this is tne first one and it's not the newest nor the oldest.
Also when I pump the brakes as cars warming up sitting in the drive idleing.(not on the road yet)the idle drops/rises but when I do hit the road afterwards.Even with car not fully warmed up.(frost still on hood)The brakes act fine.When I don't pump em they act like i floor them at just barely a touch for the first 2 or 4 times.
Thinkin there might be a vacc leak in either the booster or the check valve.

 

Well if your RPMs jump with applying brake pressure I would say you should check your engine vacuum to make sure the brake booster gets what it needs. This may just be sign of some engine trouble. Could just be a blown gasket or a loose hose.