1998 GMC Jimmy Q&A

1998 GMC Jimmy Question: What is wrong and what is the fix, sometimes when Im braking the pedal gets hard

also makes a hydraulic noise and the brakes dont work, when you push really hard they will work again -
Answer 1
Check vacuum at brake booster if ok have booster replaced. -
Comment 1
I agree with wetry -
Comment 2
I agree with goodguy. -
Comment 3
If I pull the abs fuse the brakes work fine, would it still be the brake booster? -
Comment 4
You didn't mention the ABS light was on! Have the system scanned, lots of sensors, the module, valves ect. it could be. There will be codes if you put the fuse back and drive it then scan. Or leave the fuse out but you will no longer have anti lock brakes. Most common problem is wheel speed sensor(s) or connections. But not the only one. -
Answer 2
sounds like power brake booster is bad -
Comment 1
where is the brake booster located? -
Comment 2
It is the big black round thing behind the master cylinder. Suggest towing to repair shop! I agree with everybody. -