Guys, need some help with my brakes on my '05 lancer.

Recently discovered that my brakes felt "spongy". This effect is not consistent - sometimes pedal will hold firm from moment I step on the brakes while sometimes pedal felt mushy and slowly travel down almost till bottoming out.

My first thought would be air in the brake system so i've let my mech bled my brakes twice but no improvement...
Could air be still trapped somewhere else - eg. the master cylinder?

I suspect it could be the brake master cylinder going bonkers (internal leaks? cylinder piston faulty?) but since my ride is only 1.5yrs old, maybe not...? There is also no leaks at the cylinder and the brake fluid level did not go down. The pads are quite new about a month old.

Pls help...

 

If it is spongy then I feel like there is air in it but why would there be air. Did you run low on fluid to suck air?

ROAD/RACE

 

Tks for the quick reply.

Nope, didnt run low on the fluid to the best tht i can recall... could moisture in the fluid cause spongy brakes too?

 

If the pedal sometimes slowly goes to the floor like when you’re at a red light and there is no leak it's the master.

 

yeah, when i'm stationery and I pump my brakes, sometimes it holds but sometimes it travels further downward before holding. Guess its the master then... its a shame to have the master dieing on a 1.5yr car...

 

Some updates: Managed to swap to a new master cylinder last night and my brakes are back to its normal operations for the first time in donkey months.

So indeed it was the master cylinder acting up.

 

Good you got it resolved.

ROAD/RACE

 

Before this I create a whole new thread about a very simialiar topic, I'll just let it out here. Would the brake master cyl be in/on the 75k extended coverage I got from the dealer? My pedal rarely does what fireman1 above said (though I do notice it when it does), but I definitely don't want to be caught in a bad situation and have such an issue arise...

I'm still under 70k miles, and if the warranty would fix it I'd be a happy camper!

 

It should be covered, master cylinders aren’t considered a wear item like brake pads and tires. The thing is that you have to get the repair shop to see the same symptoms that you see. Most extended warrantees will pay for repairs at independent shops if you have a local friendly mechanic just have him swap it out for you.


The things are so cheap and so important I wouldn’t worry too much about who’s going to pay for it. Just get it done.

 

^^^Thanks for the advice. I'd figure they just couldn't take my word for it and fix it. But since it doesn't happen all the time, I'm not sure if they will be able to replecate the problem. I'll see what can be done and I'll wipe out the extended warranty info too.