I got a 2000 TL, replaced brakes lines, all 4 rubber hoses, tried 3 different brake boosters, mc’s and tried swapping abs blocks(used). Bench bled, bled all 4 corners, abs fittings, junction box but no matter what the pedal doesn’t firm up. Gotta pump it a few times for it to get firm but then it gradually goes down. Same thing if you drive it. Gotta pump it once then hit the brakes for it to actually stop. Even went as far as bypassing the abs block and using a proportioning valve. Which worked consistently better but still didn’t have a firm pedal. Not sure what else to do. Looking for any suggestions

 

one of your calipers must be leaking

 

Those are also new, forgot to mention that. Oops

 

Did you do the brake booster test as noted in the service manual? sounds like that...