Ok , my brakes just started acting funky. They get super soft and slowly go to the floor, only sometimes which is strange.. There is absolutely no leaks and they worked perfect before. Also when I release the brake pedal after they go down far my idle jumps.. Could my brake booster have took a crap? I checked all the lines and hoses and there is nothing leaking at all. :/

 

Could it be a faulty check valve on the booster vaccum line?

 

Sounds like a master cylinder to me

 

That does make good sense. Why would my idle fluctuate so much "go up for a brief second" when I release the pedal though.. It really ticks me off. Previous owner had all new lines calipers(4 wheel disc), hoses put on right before i bought it a couple years ago. So at least taking stuff off will not be an issue.

 

I mean nothing is leaking and they worked 100% yesterday.. Now it is real sketchy driving it like this . Especially for something thats not leaking anything.. Boggles me.

 

The idle only jumps when the pedal comes up after the times it goes dang near to the floor.. maybe that is just it having to re suck all the vaccum back into the booster.

 

Yes. The engine is adjusting to the vacuum differences in the booster. Same thing happens when you quickly pump the brake pedal many times in succession.
the master cylinder is mechanically and directly connected to the brake pedal. The only way the pedal can go to the floor is lack of fluid in the system, an external leak, or a internal leak in the master cylinder.
An internal leak is when brake fluid is seeping past the internal cups in the MC not allowing pressure to build at the brake calipers.
You can try this which sometimes confirms a bad MC.
Very quickly and firmly apply the brakes and note the firmness of the brake pedal. Then release and this time slowly and gently apply the brakes. This time the pedal will most likely go to the floor.

 

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Sounds similar to what mine is doing - to date with no resolution
Like yours there are No external leaks

Replaced the Master Cylinder with NO Change to the symptom. Complete brake fluid flush w/ Power Motive pressure flush, used my DRBIII to "Bleed ABS" plus checked operation of all the ABS Components. I noticed the pedal firmed up a bit after "testing" the ABS Valves a few times then went back to mush.

Hope one of us finds a resolution soon

I would guess the brake systems are very similar
Mine has the three channel ABS
2003 2500 RAM w/ 5.7L

 

I have done this and it seems random if it goes to the floor or not after. Fluid level has not changed either.Also if I shut the truck off and pump them up hard , they never get soft when pressing on them. .. It kinda has me baffled.

 

Time for functional tests on ABS controller. The typical home code reader won't have that capability though......