I also have a hissing sound coming from the.

1ST OF ALL---YOU SORTA NEED TO BE A BIT MECHANICAL

THIS IS NOT A TERRIBLY HARD TASK---IT IS A LITTLE INVOLVED!

THIS MIGHT BE YOUR BEST FRIEND.........'CEPT ONE FOR YOURS

https://www.2carpros.com/questions/2007-ford-taurus-tune-up

YOU DID NOT SUPPLY COMPLETE VEHICLE INFO---SO I GRABBED BOTH "POSSIBLE PARTS" AT THE AUTO PARTS STORE SITE

Reman.; w/o Master Cylinder; w/4 Wheel Disc

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_remanufactured-power-brake-booster-cardone_20690339-p?searchTerm=brake+booster

Reman.; w/o Master Cylinder; w/2 Wheel Disc

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_remanufactured-power-brake-booster-cardone_20690365-p?searchTerm=brake+booster

YOU CAN TEST TO VERIFY WHETHER THE BOOSTER IS BAD OR NOT----SEE MY PIC

OK---I CAN SAVE YOU SOME MONEY!!!

IF YOU DON'T FULLY UNDERSTAND THE PROCESS-- JUST ASK!........"A124" WAS WORKING 5 MINUTES AGO!

https://www.2carpros.com/questions/1998-chevrolet-cavalier-there-constant-drain-on-battery-about-300-ma-now-after/page/5

KEEP US POSTED ON HOW THINGS ARE WORKING OUT

IT'S NOT REAL FUN WRITING A BUNCH OF STUFF---HEARING NO REPLY

THE MEDIC