hksnlper

iTrader: (1)

ok guys here is the problem and i can use any help.

1997 Lexus ES300 240k miles
all 4 Brakes are locking up. Here is what we changed so far. Brake Pads, Master Cylinder, Brake Booster, ABS Pump. I cant think of any thing else. You drive for a min and then all 4 brakes will lock up. If we release the pressure from the lines it works then again a min later all 4 brakes lock up. I cant think of anything. Any advise will be appreciated

hksnlper

iTrader: (1)

any one.......

LeX2K

Are you sure all 4 brakes lock at the same time? Seeing you replaced the ABS pump and the master cylinder, the only thing left would be brake lines, calipers, and the ABS computer (I don't think the ABS computer is integrated into the module).

canucklehe

perhaps a sticky caliper(s) ?

is there a brake proportioning valve on these?

hksnlper

iTrader: (1)

all 4 brakes lock up not just 1 or 2 or 3 all 4.

LeX2K

Disable the ABS system and go for a drive.

hksnlper

iTrader: (1)

already tried that didnt work

mitmaks

I'm betting on brake booster. You need to adjust shaft on the booster. Left = less brake grab, right = more brake grab.

LeX2K

You need to put the car on a lift, remove all the wheels, put the car in gear and observe. Are you sure you don't have a missing spring on the brake pedal mechanism?

hksnlper

iTrader: (1)

already checked the brakes with out the wheels and they all lock up at the same time. Check the pedal assembly and no missing parts.

LeX2K

If you start the car and just let it idle, no touching the pedal, will the brakes lock?

mitmaks

As I've already suggested, check your booster rod clearance, perhaps you have it adjusted in too far. Try screwing it out (turning it left) and it should fix the problem.

alnaimi

first sorry my english
i had the same problem and i fixed it. there is air in your abs just remove it .

ajkj

I have also been experiencing this problem. Spent lots of money replacing abs controller, master cylinder, calipers... quite frustrated.

Was there a solution that worked for you?

albertldee

curious to know the result