No brake pedal pressure after bleeding

So I bled all 4 wheels again twice with the key on this time and got minor air out of the system again but still almost no pedal pressure when the trucks running. I’ll just break down and go to the dealership and see how bad the screwing will be this time. Thanks for all the advice and help

 

Does anybody know if there is a proportioning valve on the bed of the truck that may need to bleed to get air out? I had a tundra a few years back and it had one that had a bleeder screw. I didn’t see one on the Tacoma but I also didn’t think to look for one until now.

 

2nd gen tacomas do not have load proportioning valves.

 

You're going to have to bite the bullet and go to a dealership. There is air in your ABS module.

 

This is exactly what happened.

There is an alternative method though.

Find a section of real-estate to perform a test. Preferably off road.

Accelerate to enough speed to be able to activate the ABS system when braking. Do it multiple times.

Go home and bleed brakes. Then check the pedal. Might need to perform the braking test again, or it might be done.

Had a similar issue on my friend's truck. Ended up spraying down the road with water, then performing some hard braking over that spot. Activated the ABS, forced the bubbles out of th module. Bled and GTG.

 

I'm not an expert here, so there's your disclaimer. Never done a brake job, but have done plenty of research on doing the same for the clutch on my old Pathfinder, the results of which are below. Go ahead and roast me for these disclaimers haha.

But, everyone here is talking about bleeding brakes by pumping with the brake pedal? Sounds like as much work as they've described. That will push air into the system and try to force the bubbles downward... Buy a hand pump and fill from the caliper bleeder screw, pushing the bubbles up and out of the master cylinder reservoir, in the direction the air already wants to go.

The ABS module input is why I really don't know what the hell I'm talking about though

 

I'm a big fan of the Mity Vac over the foot pump assistant for multiple reasons. It allows me to work alone and not have to shout at someone, it is faster, and it works.
It does not seem to be working with the possible air somewhere in the ABS module, however. I too am a fan of the reverse bleed procedure (pump fluid in from the bottom and suck out the top.) It works really well on my Shimano bicycle brakes, but as noted, the ABS module is a factor that isn't on bicycles (yet.)

 

I never thought of this, but it sounds promising! Of course this is the first time it hasn't rained in 9 months, so finding somewhere to skid may be an issue. I wonder what happens if you stop one wheel spinning while the car is up on jackstands? Sounds like a recipe for disaster....

 

Hahah thanks for the ideas but I made an appointment at the dealership to have the system bled and flushed with the techstream system. They quoted $129 so if it works that’s not too bad, considering the source.

 

I agree with you, you really do not know what the hell you are talking about.

 

I won’t roast you bud.

But this should NOT be done.
There’s a reason the bleeders are placed on the upper portion of the caliper.
Like you said, Air rises. It’ll want to raise UP to the bleeder.
That’s one of the main reasons you have a left and right caliper.
They aren’t usually interchangeable. And why you always want to double check the box before you leave the parts store. I always check this on reman calipers.


Doing what you said, will cause all the old contaminated fluid to be forced up through all the components of the brake system. That’s not a risk I’d be willing to take.

Again, not trying to down you man.
You were trying to help. That’s more than some would do

 

Pretty much any safe area where you can stop hard. Except jack stands.

 

Exactly what we did with a master cylinder change on a Highlander I had. A bit of a pain, but it worked.

 

I’ve done something like 500 brake jobs. Years ago I used a vacuum pump at the bleeder but the 2 person method works far better. No I’ve never tried pushing fluid backwards up into the mc reservoir.

A couple tips. If you plan on new calipers or wheel cylinders, bleed until clean fluid is coming out. So you aren’t pushing dirty fluid into the new parts. if replacing the master cylinder, they come with little caps in the ports. You can sorta bench bleed it in place. Install the master cylinder leaving the caps in. Fill the reservoir, press the pedal down, squeeze the caps in, let the pedal up, repeat a few times. Then remove the caps and install the lines. I haven’t tried it yet but I read a tip here, if you slightly depress the brake pedal, using a piece of wood or something, it’ll keep the reservoir from draining out when disconnecting the calipers or wheel cylinders. Having too much brake cleaner and fluid is better than running out, having to stop, jump in another car if you have one, going back to get more.

 

The pain for us, was everything else tried, prior to this method.

Trying to purge from the ABS module itself multiple times, then the brakes. Repetition after repetition. It was like there was a beach ball volume of air in there. Then a few trips across the wet pavement....done. That was a face palm moment.

I then more recently purchased a device which plugs into the OBD2 port. It can can activate the ABS module on a lot vehicles, as well as perform a lot of other functions. Bluetooth to the phone. However, my 2006 was not supported through that feature.

 

This is a good practice. Wedge a bar between the pedal and seat.

 

I am indeed just trying to help! I think I meant this technique seems more reasonable to fill an empty system, again if I'm wrong help me understand. Maybe I'm naive but is the plumbing on every vehicle really so perfectly arranged that there is no place between the brake and master cylinder that is perfectly horizontal or worse, a local high point?

Could you use the brake pedal to drain some of the fluid, pushing all those contaminants down and out the short way, then fill with a hand pump from the bleeder screw? The screw is at the upper portion of the caliper, but not the whole system. Having some bubbles trapped near the caliper is an easier problem to solve than pushing air that is near the master cylinder all the way down to the caliper.

edit: this'll earn me a roast. I work in engineering, and obviously not the automotive industry haha. There is a misconception that engineers know the right answer right away every time, but you'd be surprised just how much brainstorming is used to solve problems. You gotta be willing to just blurt out some ideas with a little reasoning to back it up, like I did here. I'm told I'm wrong more than I'm right, and no one cares about or remembers "incorrect" suggestions.

 

I'd rather be wrong than in the peanut gallery

 

You could drain the system.
But you never what to allow more air than necessary into the system. That is one reason, you typically bench bleed master cylinders.

As for the system being level. Nope, none are that I’ve seen.

What OP is dealing with is the ABS module. It is essentially a box with small pistons inside that “pump” or pulsate the brakes really fast to help keep the tires from full lock up.

What happens is that air gets in the module (cylinders) and gets trapped.
You can not push that air out without activating the ABS module/pistons.
Which in turn forces the air out and down the brake lines.

 

That sounds like a good plan. They'll be able to pinpoint the problem, either way.