Brakes locking up

The rod has to be adjusted so there is a very tiny amount of play before it contacts the master cylinder. You just need to confirm that the master is returning fully to it stops and the rod is not preventing that.

Does the master cylinder need to be off to adjust this? The dealership I went to said that they needed to pull master cylinder to adjust and it would be $190.00. They said that if it did not work that they would replace the power booster next. They would be questing as they did not know what the problem was. I told my niece that they would only be questing when I had the dealership on speaker phone. They called back an hour later and said that a new tech was walking by and said that it was out of adjustment by 10 mm, he fixed it and that is when they said if that did not work they would change the power booster. So if you could help me with the adjustment on the rod or what to try next I could use the help. Thank you.
William

Yes, the master has to be removed or at least pulled away from the booster some.

If the rod is out of adjustment would the brakes work at all? When I changed the master cylinder the brakes worked fine for a week and then started to act up and stick.

If the master is not able to completely return to its stop, it will not release pressure and it will build up a keep the brakes on.

Would the brakes work fine if the rod is out of adjustment and can you tell me how to check and see if the rod is out of adjustment and how to correct it?

Can you explain to me how to check to see if the master cylinder is returning completely and how to adjust the rod?

You need to have about 1/16" of free play before contacting it.

Is that between the power booster and the master cylinder. I can take it apart and put it back together with no problem, but I have never dealt with this before.

There is a special tool to check the push rod length is correct, but as wrenchtech says you need a small amount clearance so the brakes do not bind up with residual pressure.

If the rod is out of adjustment would the brakes work fine for a week and then lock up or would that be something else. This is what happen and that is why I am asking so many questions as I am trying to understand this.

When the brake are locked up, safely raise each wheel to see if all wheels are locked up, if so then its the adjustment at the master which can be checked simply be loosening the masters mounting bolts, if the wheel starts to roll then that is the problem, if you only have one wheel that is locked the problem is the rubber flex line need to be replaced, if one of the rear wheels are locked and it has drum brakes remove the rear wheel and look and the brake shoes they could be falling apart.

Please let me know what you find.

Best, Ken

After driving the car the left front and right rear are locking up. I have changed the left front brake caliper as it was sticking when I tried to push the piston in and rotor along with all four brake hoses. I have also changed the master cylinder, could you give me an ideal of what to do next. Thank you William

This sounds like the ABS module and valve are bad and need to be replaced.

It appears that it was the ABS module thanks for your help

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