I purchased my '90 GXL about 3 months ago, and I knew when I 1st drove it that the brakes didnt feel good at all. I basically feel no pedal pressure, almost like they arent power assisted brakes. I have to push the pedal very hard and far before I get much response. I have replaced pads all the way around, as well as bled the entire system, with not too much change in pedal feel. I will be changing my master cylinder soon, as I have a new one laying around anyway, but Ive had a master cylinder go bad on me before, and this doesnt feel quite the same. If I push the pedal down and hold it, It doesnt seem to slowly bleed pressure and go to the floor, it stays about where you have it. I am not leaking fluid anywhere, resavoir stays at a consistant level. I just wanted to ask, has anyone had the brake boosted itself go bad? Like I said, it seems as almost I have non-power brakes, thats how hard I have to push the pedal, and it gives almost no feedback until about 1/2way down.

 

is there a leak in the brake booster vac hose?

 

Sorry, forgot to mention I checked for leaks in the vac lines to the booster, there is none.

 

I am sure that there are better brake experts on here than myself, but, if you are not seeing any leaks from the master cylinder, then you may have air in the master cylinder itself that is not being purged when you do the normal bleeding of the brake lines. In other words, you may need to "bench bleed" the master cylinder to get the air out. Not having done this in a while, I will leave it to others who can explain just how to do this. I just thought I would throw that in to get some ideas going on this thread.

 

From past memory. When car off depress the pedal numerous times to remove all vacuum. Hold foot on pedal and start the car. The pedal should move down rapidly. If it doesn't move, or sinks slowly, look for a possible obstruction.

 

This is correct. What you're looking for is if the pedal goes down upon start-up. If it does not, Replace the power booster.

 

could be also worn/expanded factory brake lines. Lets face it at 15 years old the factory rubber brake lines are on their last legs. More so if you are in a climate that see's snow.