techweenie
Member
- Joined
- December 8, 2017
- Messages
- 12
- Reaction score
- 3
- City, State
- Grand Blanc, MI
- Year, Model & Trim Level
- 1994 Explorer Limited
I need help! I've been trying to bleed the brakes on my 94 Explorer with 4WABS for over a month and haven't been able to do it. The symptoms are spongy pedal, low pedal with engine running, and constant stream of small bubbles when bleeding. I figured it had to be air in the ABS pump, so I bought the bleeder tool and used it. That actually made the problem worse and I had NO pedal after that. I then went to a junkyard and pulled another ABS pump and installed it. Ran the bleeder on it, and I was back to square one with the low spongy pedal, but at least I had SOME pedal again. No air whatsoever in the front lines, but a constant stream of tiny bubbles remained in the rear. I then did as much research on this as I could and determined it must be a stuck valve in both pumps causing fluid to fill the accumulator rather than go to the calipers or drums. Rather than gamble on another junkyard part, I ordered a brand new pump from ebay. Installed that today, and STILL THE SAME SYMPTOMS. This time I'm getting a steady stream of tiny air bubbles at all four wheels. I have the factory service manual and I've followed it to the letter on diagnosing the low pedal and bleeding procedures. I'm using the 2 person down/up method without pumping up in between (tried pumping up as well, no different). I tried vacuum bleeding but couldn't get that to work. I put a new master cylinder on it but that didn't help. It did solve intermittent brake light function though (the old one didn't have enough return pressure to keep the switch activated). I put a vacuum pump on the booster and it held vacuum. I don't know what else I can do!