IsaacMTSU wrote: The ABS has a pressure dump that sends fluid into an accumulator instead of the line when a certain pressure is reached. This pressure is seen as "way too much brake pressure for the current speed" and allows the pedal to sink into the floor when at standstill instead of blowing a line. When ABS is activated the fluid is pulsed into this accumulator (really small amount) instead of going to the line. That's its method of ABS control. So, the ONLY way to properly bleed that accumulator when you need to bleed the lines is by using the factory scan tool to cycle the ABS dump valve to fill the accumulator with fluid while you are bleeding. You can do it the redneck way and make the ABS cycle a bunch on some gravel then re-bleed.
All true - good point.
Another potential failure point is the method (various) for returning the brake fluid out of the accumulator back to the reservoir - some models use a pump, some just use accumulated pressure - either way, there are additional failure modes involved (pump failure, solenoid failure, etc).
Another failure mode - the accumulator pictured below (potential diaphragm rupture).
Just more things to be thinking about when you're trying to put your finger on the specific culprit...
IsaacMTSU wrote:Chris, after I saw your post I called my uncle. He's ran the Gatlinburg city service center for like 500 years. He said it's normal on a GM, Ford, or some Dodges with ABS. The ABS has a pressure dump that sends fluid into an accumulator instead of the line when a certain pressure is reached. This pressure is seen as "way too much brake pressure for the current speed" and allows the pedal to sink into the floor when at standstill instead of blowing a line. When ABS is activated the fluid is pulsed into this accumulator (really small amount) instead of going to the line. That's its method of ABS control. So, the ONLY way to properly bleed that accumulator when you need to bleed the lines is by using the factory scan tool to cycle the ABS dump valve to fill the accumulator with fluid while you are bleeding. You can do it the redneck way and make the ABS cycle a bunch on some gravel then re-bleed. Might have to do it a few times though to get the air out of the accumulator.
So, I'll try that before I buy anything else!
Its an absolute PITA to get the air out the ABS block, as I recently discovered when my brakes decided to self bleed last year. The redneck solution didn't work (too much air) and I just took it somewhere that had a Tech II computer to let the system self bleed.
Point is, I'm sure Ford has a similar tool - maybe its cheaper than a Tech II tool.
The big problem I've always had over the years is having the system go into Ice Mode when braking too heavily during autocross. Only way I found to bypass it was to just stay out of the ABS (I don't like pulling the fuse - I like some insurance against flatspotting expensive race tires.). Not sure if the S10 has similar problems, but I think there are some similar components. I was thinking this was your problem when you originally posted this, but it seems like you did find a leak.
