Brake Problem (Help!)

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Vehicle: 2004 Toyota 4Runner Limited 4-wheel drive 4.7L V-8 with 130,000 miles.

Problem: We replaced the front left caliper because it was stuck. New caliper, new brake pads, also replaced back right rotor. Bled the brakes using correct method (farthest away from master cylinder to closest)until nothing but clear, bubble-free fluid came out and double checked tightness of all the fittings and looked for leaks. Now the vehicle can BARELY stop when it is just idling in gear when the pedal is pushed to the floor. Pedal rarely builds pressure and is very squishy, going all the way to the floor. If you pump it enough the ABS, VSC and some other light comes on, dings, and then goes away. We bled the system twice to try and correct the problem.

What is going on? I've never had this happen before when doing brake work. I think it sounds like air is getting in the system but I don't know...I checked every fitting and they were plenty tight. No leaks either.

On the front right caliper when installing new pads we used a C-clamp to compress the pistons back in place as usual, but 1 of the 4 pistons was rusted more than the others and wouldn't go fully in (stuck about 2mm out) no matter how much force we put into it. Could forcing that and getting rust in there be enough to cause an air leak?

Any help would be greatly appreciated.
 
Its not a good idea to reset caliper pistins on an ABS equipped vehicle unless you open the bleeder on the caliper first. You may have pushed junk into the antilock controller. You can isolate your problem by making a couple of 'plugs' with a short length of brake line. cut a piece of brake line with the same fittings ae your master cyl. crimp the line to make 2 plugs. install these in master cyl and step on the brake. If you have no pedal still, the master cyl is bad. If you have a good pedal, abs controllers are not cheap.
 
You may simply need a scan tool to bleed the ABS. You could also try doing it with the car running... not much to lose.
 
Originally Posted By: Lethal1ty17
Vehicle: 2004 Toyota 4Runner Limited 4-wheel drive 4.7L V-8 with 130,000 miles.

Problem: We replaced the front left caliper because it was stuck. New caliper, new brake pads, also replaced back right rotor. Bled the brakes using correct method (farthest away from master cylinder to closest)until nothing but clear, bubble-free fluid came out and double checked tightness of all the fittings and looked for leaks. Now the vehicle can BARELY stop when it is just idling in gear when the pedal is pushed to the floor. Pedal rarely builds pressure and is very squishy, going all the way to the floor. If you pump it enough the ABS, VSC and some other light comes on, dings, and then goes away. We bled the system twice to try and correct the problem.

What is going on? I've never had this happen before when doing brake work. I think it sounds like air is getting in the system but I don't know...I checked every fitting and they were plenty tight. No leaks either.

On the front right caliper when installing new pads we used a C-clamp to compress the pistons back in place as usual, but 1 of the 4 pistons was rusted more than the others and wouldn't go fully in (stuck about 2mm out) no matter how much force we put into it. Could forcing that and getting rust in there be enough to cause an air leak?

Any help would be greatly appreciated.


I had a power brake booster go bad on my Buick. The pedal went right to the floor with the engine running, and I had very little braking. With the booster disconnected from the engine my braking returned. The pedal stayed high and stiff, and the car could stop from 30 mph just fine.

Try this test: With the car off, pump up the brake pedal, then press firmly. If it's the M/C or air in the lines, the pedal will sink to the floor. If the pedal doesn't go down, then rule out those components.
 
If the master cyl was OK before, why would it now be faulty?
I sure don't like to hear about pushing that old fluid back into the system. Same for the stuck caliper.
You did a partial job and got partial results.
 
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