I recently bought this truck a 1997 F150 4x4 and everything was working great until one day driving to work the brake pedal would start to pulsate and the truck would not stop. I had to hit the emergency brake before slamming into the car in front of me. This problem is very intermittently. Soon after that i replaced the brake master cylinder and thought that would solve the problem. I recently had the speed control recall done on the truck and after that is when i started having problems...not sure if they are related. The ford dealership where i had the recall done assured me they were two seperate things. I was wondering if my ABS is acting up but i have no idea where to start looking. When the problem occurs the pedal will catch and release over and over and kinda of make a popping sound. The pedal never actually goes to the floor. Any advice would be greatly appreciated.

Thanks.

 

Welcome to the forum! It does sound like an ABS issue, because thats exactly what the pedal does when the ABS is activated. This may not help anything but have you tried unhooking the battery for a few minutes? Sometimes it just needs a reset and will work correctly. If that doesn't work, its probably the ABS sensor on the rear axle.

If I'm correct in remembering this, your truck since its a '97 only has rear ABS, and therefor only has the one sensor. If reseting the computer doesn't work I'd think about replacing that sensor.

 

I just posted the exact same problem before you under "ABS Problem".

To avoid a collission, remove your ABS fuse, this will bypass the ABS.

I hope someone has a good answer for the both of us.

 

97's had 4 wheel ABS as an option.
If you have rear drums, it's RABS, if you have read discs, you have 4 wheel ABS.

It does sound like an ABS problem.

 

I have 4 wheel disc. I think the sensor is in the differential, OR is there a sensor for each wheel?

 

^^^ There is a sensor in each of the front wheels and one on the rear diff. if you have 4 wheel disc.