Brake help on my 86 gt

[Desperado]

ok guys this is driving me nuts. my brake light is on in the dash. the ebrake switch is not setting it off. if i unplug the sensor on the proportioning valve the light goes out. what could be the cause of this. what do i need to check to get it fixed......


the brakes seem to work good. have to really stomp on them to get the wheels to lock up. pedal seems alittle low on the floor. i have tried bleeding them. do i need to bleed them more? please help


thanks

[FoxChassis]

Does the brake pedal have a lot of pressure (hard) or does it sink to the floor a bit (soft)?

I'll assume that since you said you bled the brakes that you also added fluid to the reservoir.

[Desperado]

they seem alittle on the soft side. it stops fine but seems low on the floor and soft. i wouldn't think much of it but the light is.

so what can i do to help this and get the light off? i can try to re-bleed the brakes.

[Paul86gt]

sounds to me like you have a vacum leak in the break booster line or your break booster is bad.

[Desperado]

would a bad brake booster still let the brakes have easy action. i mean it gets stiffer close to the bottom but it nevers goes to the floor.

[Paul86gt]

it would be like pushing the brake with the engine off, kinda soft at the top and harder as you push it and if you pump it it gets harder.

[Desperado]

if i pump the brakes while at a stop light it is the same it never gets any harder.

[frdfandc]

Sounds like the proportioning valve is starting to fail. Are these the original booster/master cylinder/proportioning valve on the car???

If so, I'd probably would install a new proportioning valve for the light, and a new master cylinder for the soft pedal.

[v8only]

How sophisticated is that sensor?? I'm almost guessing it's just a fluid level sensor.

Aside from the work that your brakes need, make sure you are topped off to the correct fill line on the resevoir.

[FoxChassis]

You should never "top off" the brake fluid unless you're in the process of bleeding the brakes (and only after a 'fresh' brake job) or the fluid is leaking somewhere in the system. In a normally operating brake system, low fluid level indicates the front pads are worn and in need of replacement.

[v8only]

Not completely true,... in my experience.

On my toyota tacoma, as the pads wear, it has a HUGE tendency to suck down the fluid level with the pad wear. The level sensor is set fairly high. As a result, I have to top off (to the fill line) the resevoir maybe every few months to keep that light off.

I thought this was a problem at first, but looked into it, and it apparently is common, at least with the tacoma's. they recommended you partially drain or "catch" the fluid when you compress the c clamps for a brake job, so that it doesn't spill over the top from the fluid that has been added.

[FoxChassis]

That might be common with Tacomas but that is not common with the cars that this 'site and message board is dedicated to. ;)