Mechanics

WAGON BRAKE BLEEDING AND LOAD SENSING VAL

1993 Toyota Camry

Brakes problem
1993 Toyota Camry 6 cyl Front Wheel Drive Automatic 215, 00 miles

The brake pedal on my Camry wagon continues to go to the floor with no loss of fluid. Brakes were great until today, when I replaced a short section of line due to rust. This was a rear brake line which runs between a coupler under the rear seat drivers side, and the LPSV (load pressure sensing valve). I replaced one of the two lines, and have bled all four corners AT LEAST A DOZEN TIMES at the bleeders. There are absolutely no fluid leaks. I suspected my master cylinder might have blown seals in the process, so I replaced with a brand new master cylinder. Problem did not change at all. Pedal has spongy pressure but drops to the floor. Car won't stop and is not driveable. Do I have to somehow bleed the LPSV? Is there a unique bleeding procedure with this car? If there is still air in the system somehow, wouldn't I at least have spongy, working brakes? HELP PLEASE! THANK YOU!
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Mbridges2
October 12, 2008.



Open up the back wheels and inspect the wheel cylinders for leakage -No leakage-try bleeding the system again to inlcude the LPSV. Still no pressure and still sinking its pointing to the new master cylinder leaking internally

Rasmataz
Oct 12, 2008.
Thanks very much for the reply.

1)Already checked for caliper and piston leakage. None.
2)Absolutely no drop in reservoir fluid level despite *hundreds* of pedal pushes. Can air leak, but not fluid?
3)How do I bleed the LPSV?
4)When I replaced the master cylinder, I disassembled the old one to inspect the seals. Seals looked perfect and the inside of the cylinder looked pristine. New master cylinder displays identical pedal feel and pressure issue.

Thanks again.

Tiny
Mbridges2
Oct 12, 2008.
3)How do I bleed the LPSV? Bleed this one 1st then RR/LR/RF/LF. When you installed the new master cylinder did you bench bleed it?

Rasmataz
Oct 13, 2008.
The LSPV cannot be bled because it's completely rotted out. I have bled the all four brakes multiple times in the correct order. I bench bled the master cylinder thoroughly. Brakes are still extremely weak and undriveable. Why can't I bypass the LPSV entirely? I'm desperate. Please keep in mind that my brakes worked great until I replaced a short section of line going into the LSPV. Thanks very much.

Tiny
Mbridges2
Oct 18, 2008.
What did you end up doing I am having a leak issue with my LSPV I would like to bypass it

mbridges2 Posted: Sat Oct 18, 2008 10: 33 am Post subject: The LSPV cannot be bled because it's completely rotted out. I have bled the all four brakes multiple times in the correct order. I bench bled the master cylinder thoroughly. Brakes are still extremely weak and undriveable. Why can't I bypass the LPSV entirely? I'm desperate. Please keep in mind that my brakes worked great until I replaced a short section of line going into the LSPV. Thanks very much.

Tiny
ALFcentori
Dec 15, 2008.