Toyota Celsior 2001 4.3

I changed brake pads and lost the brake pedal. Symptom is as if there is air trapped. When engine is not running, pedal is fine. When engine is running the pedal goes to half way down (brakes work) then slowly sinks to floor. I have blead & better blead in every wheel combination possible. Have had system pressure blead & suction blead in a garage.  Stripped & pressure tested master cylinder, it's ok. . Changed ABS unit, same problem. Feel as if air is trapped in ABS. Got Smartstorm computer program to check ECU, no faults. The programmer did say that the air ABS bleed function was not available for this vehicle. I have tried braking hard on dirt track. Can anyone help resolve. Had vehicle at Lexus, they can't fix it.

Cheers Graham

Hi Graham,

Just a thought,

Even though the master cylinder was pressure tested, was it bench tested as a bench bleed could reveal internal issues that might not be apparent during a standard pressure test.

A bench bleed involves removing the master cylinder from the car and simulating its operation while forcing air bubbles out through a dedicated port.

It will help to identify internal leaks or trapped air within the cylinder itself. 😄