I’m pretty sure that means a bad master cylinder.
@Nevada_545 's suggestion that the booster-to-master rod is the wrong length sounds plausible now.
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If that indicates a faulty master cylinder then all of the master cylinders I’ve put in were faulty cause they all did the same thing
Since the wheel speed sensor is broken & it’s telling the modulator to pulsate then when it pulsates is it pushing brake fluid into the lines?
Even the one that “worked” (no locking) but the pedal sank too low?
Is the tip of the master cylinder push rod adjustable like the one in this diagram? If so you must have it properly adjusted when installing a replacement master cylinder.
With an open circuit and the warning light on the ABS system is inactive/disabled.
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Yes even the old master cylinder was leaking between the back of it & the brake booster
That is a brake booster not a master cylinder & yes the rod in the booster is adjustable.
That is the brake booster, make the necessary adjustment to the master cylinder push rod located in the booster.
With an estimated guess i think you’re right about the booster rod but I’ll find out soon enough. It’s cold working outside when it feels like -9 Degrees
The ABS is a fail safe system which means any failure puts it in an inoperative mode that allows the rest of the brake system to operate as if the vehicle never had ABS to begin with. So if you have an ABS light, then ABS is not causing this issue. It should be repaired however.
I doubt that adjusting the booster rod is going to fix your problem. I think you need a new booster. You may also need another new master cylinder because based on your descriptions, the booster has been damaging all the previous master cylinders and the current one is probably damaged by now too.
I doubt that I need a new booster but i might have damaged the master cylinder but I’m gonna go with the theory that I don’t need a new one for right now because if I lower the booster rod to the required length & the brakes start slipping then i know that i need a new master cylinder but the booster works just fine & the rod being too long would explain why the brakes lock up after the car is warmed up
Plus the master cylinders were leaking brake fluid between the MC & booster before even putting the new ones on so nothing has changed from how they were acting when I first got them
Could it be that the booster’s vent ports were plugged with ice?
I highly doubt that it could of been plugged with ice cause I’ve let the car run for a while multiple times with the heat inside running to where if there was any water inside or outside on the vehicle then it would of melted
Let us know when you figure out that you do need a new booster and finally solve your problem. In the meantime, it’s your money and time.
Another reason you keep seeing fluid there is that you now have fluid in the booster that keeps showing up. There should never be brake fluid between the master and the booster.
How do I adjust the rod in the brake booster when there isn’t any threads to be seen?
Look inside where the brake pedal’s mechanism pushes through the firewall.
I can see something inside there but the rod moves all over & no matter which direction i turn it, it won’t go in or out no matter how much i turn it
3 hours ago you said your push rod was adjustable. Did you mention before that you verified the brake pedal free play? You may have no choice other than replacing the brake booster. First measure and compare the push rod cavity depth in both master cylinders, be sure you are getting the correct master cylinders.