Ok, So i have a 1998 GMC JIMMY 4 DOOR and the car has had the best maintenance to my knowledge, th vehicle used to stop on the dime when the brake was applied. now the pedal seems to go to the floor , the interesting issue is THAT MY MOM TOLD ME WHENSHE PRESS THE PEDAL TO BRAKE SHE HEARS AIR (I WAS LIKE HUH LOL) I DROVE THE VEHICLE AND PRESSED THE PEDAL AND IT HAPPENS ONLY WHEN B PEDDLE IS PRESSED

( VEHICLE IS SOMETIMES ROUGH AT IDLE THEN PLACED IN N)

 

Bump SOMEONE PLEASE Write sometHING LOL TO MANY VIEWS NOT TO HAVE ON REPLY

 

Here's a hint... Turn off CAPS lock! No one wants to be yelled at.

If you hear air, your booster is leaking and in need of replacement.

If the pedal goes all the way to the floor, you either have a leaking line or too low of a fluid level in the master cylinder, both of which would allow air into the lines. You could try bleeding the brakes. This condition could also be caused by a bad master cylinder.

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