[rovermech]

I am a retired mechanic with over 60 years in the trade and when ABS came along the sinking brake pedal problem seamed to get more frequent I found out when bleeding the brakes if I clamped the flex pipe & opened the bleed nipple to release the fluid when changing pads etc then remove the clamp from the brake pipe to bleed the brakes never had the problem it is the pushing the fluid back through the system that's the problem you can flip a seal in the ABS or master cyl that's my thinking anyway but what do I know I'm 84 years old