I was on the interstate going 60 mph my 92 Cherokee Larado stuttered a few times. I thought trans problem. Then,I thought, lately my anti-lock brakes were acting "funky". I could start out and as soon as I applied the brakes the anti-locks would act as if I was on ice.After that initial event it would go back to normal for the rest of the drive. Last week the brakes went out totally. Then applied the brake immediately after it was fine. Has anyone experienced this?Does anyone know what the problem is and how to fix it?

 

Did you have the brakes applied while on the interstate? The ABS module doesn't apply pressure to the brakes. It applies pressure to push your pedal back. If the brakes weren't applied on the interstate then it isn't the ABS.

 

No I didn't apply the brakes.It is hard to determine what the stuttering was. After some thought maybe the engine was missing. I plan on changing plugs. But, i still have a problem with my brakes. When starting out first thing in the morning, sometimes my brake pedal will rapidly pulsate when I apply the brakes. After the first time its fine.Is there a brain for the brakes and could it be the sensor isn't picking up tire rotation?

 

Could be a warped rotor? If it's grabbing w/o bein on breaks then that's odd. Could be something loosened enough to grab when jarred over a bump or somethin? If it stuttered then it could be somethin in ignition/firing/exhaust system? Like a TPS issue or possibly o2 sensors? Try throwing it on a code reader if ya want. Even if the CEL isn't on doesn't mean there isn't a code stored in in there.. Idk..

 

This is completely false. The abs system overrides the brake pedal to apply the brakes. It is used to "pump the pedal" in an emergency situation. You have no traction with the tire locked up, so the abs system alternates (very quickly) between locked up and rolling to stop the vehicle quicker.


If you feel like the abs is activating while you are going down the road without applying the brakes, you need to start checking wheel speed sensors. It sounds like your jeep is getting a false reading and the abs is activating because it /thinks/ a wheel is locked up....

 

Gee.... Thank you for the lesson in how ABS works. However I have yet to see a vehicle start randomly "pumping" it's brakes without touching the brake pedal.

To correct your "lesson" the ABS isn't "pumping the brakes" wildly. It reduces the pressure to the brake of the wheel that is skidding until it sees an acceleration, then it increases the pressure until it sees the deceleration again. This is done with valving using the pressure from the master cylinder. The ABS pump is a subliminal source so the brake pedal doesn't travel to the floor from releasing pressure. That is why you get the "pulsating" pedal feel when the ABS is active.