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I'll start this off addressing all the comments that I know I'll get.
I have literally searched every thread on here and read them all trying to figure out what the hell is happening to my brakes. Yes I am bleeding both screws, yes I'm bleeding in the order from the mitsu service manual. Outside first on each calipers and order Passenger Rear, Driver Front, Driver Rear, and Passenger Front. I have bled solid 5 gallons through the system. I have pressure bled with motive bleeder, vacuum bled with multiple different tools, pedal bled. Tried all of those methods with the car on and off. I bought a scan tool to run the ABS module, turns out it doesn't work with the Evo, but it does with all 5 of my other cars.. Go figure. Went to gravel lot and cycled the dog sh*t out of the ABS module and bled again. No luck
So the backstory...
I bought the car 2 years ago and have never had an issue with the brakes other than being squeaky as sh*t and waking the neighbors up in the morning. But the pedal has always been solid as a rock. Took the calipers off to powder coat them, let the whole system run dry probably.. If there was any fluid left in the system it wasn't much. Car sat like that for weeks. Got the calipers back on and have bled the living crap out of them and my pedal feels like absolute sh*t.. I'm kind of losing my mind at this point, and my state is running out of brake fluid.
I rebuilt the calipers with girodisc seals and dust boots. I did not split the calipers when I powder coated them. I did take the pistons and seals out tho and masked everything off. I know there is an o-ring in the back calipers if you split them, however, I would think that the temperature from the powdercoat wouldn't be hot enough to melt them, especially compared to the track which this car has seen alot of with hard braking.
Also there is no signs of leaking from anywhere, and definitely not where those orings are.. Some other things I've tried
Pads are OEM brembo pads with their shims. Shims look completely flat and not damaged
New brembo bleeder screws
Stainless Steel goodridge brake lines
Bled the abs module by cracking the lines with the motive bleeder connected
Bled the master cylinder the same way
Replaced the master cylinder (with a raybestos unit from rockauto)
Check all pistons with pads out to make sure they are moving
I'm sure I'll think of more to say and I'll either edit the post or post again. Any help is appreciated. If anybody gives me the idea that solves this issue, I promise to make it worth your while with paypal. Minimum of $50 and depending on how close I am to burning the car to the ground it may be more! Please help!
I also promise to post the solution whenever it is found because I'm sick of reading threads that end without saying how they fixed their issues.. Lol
Last edited by DaytonWells; May 10, 2020 at 09:16 AM.
From my experience of removing the calipers and draining the whole system. I had to bleed it out with new pads / the pistons completely seated to get good pedal feel back. My theory being air was getting trapped in the cylinder bores of the calipers and the only way to get it out is if the pistons where completely seated when bleeding. You didn't mention if your pads were new or not, but if you are starting out with the pistons extended a bit try getting them fully seated and bleed from there.
From my experience of removing the calipers and draining the whole system. I had to bleed it out with new pads / the pistons completely seated to get good pedal feel back. My theory being air was getting trapped in the cylinder bores of the calipers and the only way to get it out is if the pistons where completely seated when bleeding. You didn't mention if your pads were new or not, but if you are starting out with the pistons extended a bit try getting them fully seated and bleed from there.
Pads are somewhat new. Not new after the powder coat though. Only 5k miles on them at the most, plenty of thickness left.
As for the bleeding with the pistons seated, that sounds like an interesting theory for sure. And they have been somewhat extended probably for the entire time i've been trying to bleed. Next time I go out there I'm going to give that a shot. Do you compress them all the way back in and use a pressure bleeder? What method do you usually use
Pads are somewhat new. Not new after the powder coat though. Only 5k miles on them at the most, plenty of thickness left.
As for the bleeding with the pistons seated, that sounds like an interesting theory for sure. And they have been somewhat extended probably for the entire time i've been trying to bleed. Next time I go out there I'm going to give that a shot. Do you compress them all the way back in and use a pressure bleeder? What method do you usually use
Yah I compressed them until they were completely flush. I have Russel Speed bleeders for solo bleeding. I will note that the FSM calls for the engine to be running while bleeding so I started doing that as well.
If you master cylinder went dry it needs to be bench bled. If you don't, you get what is happening to you. You will always be pushing air into the system. There are alot of videos on how to do this but basically you need to turn you master cyl. Into a closed system. Remove lines and attach hoses that go back into reservoir. Slowly depress many, many times until air is visually gone. If I'm right the fluid will be very airiated the first several times of doing this. Hope this helps. Only other possibilities are air entering somewhere but I think bench bleeding will fix your issue.👍🏻
I removed all the calipers and had system basically dry. New pistons, bleeders, lines, pads, rotors etc. For me, a mittyvac and several rounds of manual bleeding worked fine. Same for the clutch. Also need to work your way from the farthest point towards the brake master cylinder. Then had to do it all again when I swapped out to Evo X front calipers. Also you will need to pull a lot of fluid to each corner to get this right. Its not going to be just a little bit of fluid and bubbles.
As said, you need to bench bleed the master. You can try what was said, if you can get hoses to seal.
Have not had to do it in the evo but this is Toyota's way of bleeding a master.
Takes 2 people.
Remove brake lines from master, depress brake pedal, put you fingers over the holes in the master where brakes lines go in to create a seal. Let the brake pedal up. Do that a few times, reattach brake lines to master then bleed brakes normally.
What I hate about this, is it makes a mess. Brake fluid will shoot out when pedal is depressed, try to use rags or what ever you can to catch as much fluid as you can.
I will run to the auto parts store on my way home from work tomorrow and pick up a bench bleeding kit. I did do it before I put it in the car but I only had one hose/plastic fitting because my kit was missing the other one so I did it one port at a time with it in a vise. Looking back on it I suppose I could have missed some air in it, I'm willing to try anything at this point haha.
Have any of you bench bled installed in the car using the brake pedal? Seems like that would get better travel anyways.
Also, I just got back in from the garage and bled with the pistons compressed and I did get alot of air. Especially out of the driver rear outside bleeder. As of right now the pedal feels much better but I can still push it all the way to the floor if I try. It does engage near the top though which is a step in the right direction, just doesn't have that solid feel.. It makes sense that I would be getting air each time I bled if the MC wasn't bled properly, so what the hell, I'll give it a shot tomorrow.
Last edited by DaytonWells; May 10, 2020 at 02:49 PM.
As said, you need to bench bleed the master. You can try what was said, if you can get hoses to seal.
Have not had to do it in the evo but this is Toyota's way of bleeding a master.
Takes 2 people.
Remove brake lines from master, depress brake pedal, put you fingers over the holes in the master where brakes lines go in to create a seal. Let the brake pedal up. Do that a few times, reattach brake lines to master then bleed brakes normally.
What I hate about this, is it makes a mess. Brake fluid will shoot out when pedal is depressed, try to use rags or what ever you can to catch as much fluid as you can.
Yeah I've got plenty of microfiber towels that absorb brake fluid great thanks to amazon haha. I may just try that tomorrow because I don't feel like stopping at the autoparts store to pick up the kit.. This virus makes everything too difficult
If it feels good then gets bad after awhile you have a leak. Bottom line. Possibly a bad master but since you said it was replaced I will assume its good. It's possible to have air leak in but no fluid leak externally. Rare, but I've seen it. In your situation I would crack all 4 corners loose with wheels off and a clear hose attached to bleeder to get and idea what corner has the most air and then go from there. Or obviously if you have something like a mighty vac, you should be able to find the problem quickly. To be clear, without a pressure bleeder of some kind, pump pedal and crack bleeder open and then closed before pressure is gone, to not allow air back in then release pedal. Its vital you have a clear hose attached to bleeder to see how much air is coming out. Good luck and keep us posted
I ordered a master cylinder bleeder kit, it should be here tuesday. Don't feel like going to the autoparts store anymore. Amazon had a really nice kit with metal fittings that'll fit the rest of my cars too so I guess it's worth the wait.
All you need to do is use a proper diagnostic tool and activate the abs while bleeding the system... No other way. Otherwise you will have air in the abs unit
All you need to do is use a proper diagnostic tool and activate the abs while bleeding the system... No other way. Otherwise you will have air in the abs unit
I've never tried this myself, but can you use Evoscan -> Select ABS ECU -> Actuataors -> Activate Solenoid Valve (RR, FR etc.) to accomplish the same thing?
I've never tried this myself, but can you use Evoscan -> Select ABS ECU -> Actuataors -> Activate Solenoid Valve (RR, FR etc.) to accomplish the same thing?
I've tried using evoscan to do this but I didn't have any luck. It basically said the same thing as my scan tool. That it couldn't connect to the ABS module and this scan tool works with all of my other cars to cycle the abs pump. ABS works fine though and I cycled the hell out of the module in a gravel lot so if a bench bleed doesn't work I'm going to look more into ABS.
I'll update everyone tomorrow when my bench bleed kit gets here.
May 10, 2020, 09:10 AM
Brake Bleeding Nightmare
