2015 evo x gsr 39,000 miles..... just recently had someone do a brake fluid flush on my car, guy used a power bleeder plugged into an air compressor. 2 days after i noticed my parking brake light comes and goes during heavy acceleration. when i was doing the oil change, i noticed a good amount of brake fluid underneath the vehicle, after tracing it looks like it's coming from the bottom of the reservoir. i thought to myself maybe the guy had spilled some brake fluid during the flush, cleaned mostly everything with brake cleaner. checked again today, underneath the car looks to be okay, no sign of leak, but looked in the top noticed the sealant around what im assuming is the clutch master cylinder (picture attached) has a little bit of moist on it. not sure if it's normal. also noticed liquid on the main harness underneath the reservoir (picture attached).

anyway car feels great, drive the same, no clutch pedal issues whatsoever.

any help on this would be great. new to this community. had an old lancer before this.

maybe brake fluid on main harness?

this part has the moist sealant

 

All mitsubishi EVO's have a 100k warranty on the AYC pump, that may be the issue you are experiencing.

 

I don't know exactly what could be leaking. I would check for a bleeder or something that might need to be tightened. But 2 things..


1. Hopefully they weren't careless with leaving any brake fluid on the caliper finish. That will destroy the nice shiny red. My previous owner had the CMC replaced and apparently they left some brake fluid on the rear calipers. They peeled really bad..


2. Before i say this, this could have nothing to do with your issue.. I'm not sure how that machine works. But we sell brake fluid exchange machines (flush) machines. They pressurize the brake system like the master cylinder would and then you go around to each bleeder, open it, close it, and move to the next one.. But you can adjust how high to turn the pressure up to. Ours can be adjusted from 0 psi up to about 60psi. You should really want to be in the 10-15psi range if possible. With some complicated ABS systems you may have to turn it up to 30-40 to get everything to operate like normal. If it turns out to be some leak or something that you have to replace. Maybe you could see if they had the pressure turned way up and it caused some damage to a seal or part.

 

And the AYC pump is in the rear.. So it wouldn't be leaking there. Plus it doesn't use brake fluid.

 

The Stock CMC on the X is failure prone. I have a 2013 GSR. My stock CMC failed around 65k with the same symptoms. I then made it to about 80k and the recall unit failed. I then moved to the Evo IX CMC with MAP adapter kit. no more issues. You'll do well to just replace it with an Evo IX CMC now, as the stock plastic CMC will fail.

 

#2 is most likely it. my guy must have set the psi too high.

I did find out where the leak is coming from. It's one of the lines that's connected to the CMC. Not exactly sure where it connects to, but it started out as hardline from the CMC then to a soft line. Mitsubishi sells the part oem together (hardline and softline). As soon as i step on the clutch, brake fluid, squirt out of the seal that connects from the hard line and soft line.

 

I recently replaced the CMC on my GSR. Its got the magnus kit and its running the evo 9 CMC. I noticed i was slowing losing fluid in the reservior, almost like when brake pads wear. I kept looking for leaks, but never found any. One day the brake light came on, but it would go off for a few days on its own. Another day i was driving and i noticed my pedal felt softer than normal. By the time i got close to where i was headed, i had lost all pedal pressure and it went to the floor. luckily i was able to limp it to a autozone. i discovered the fluid was so low in the reservior, that it was exposing the pickup tube for the cmc, causing air to get pulled in everytime i pushed the pedal. i filled it all up and was able to pump the pedal up to get pressure to drive home. the next day i bled the slave and had no issues for several weeks, except for the mysterious fluid loss. Then i was driving again and lost the pedal, even though this time i had been topping the brake fluid off every other week. I got the car home and decided to pull the cmc. i discovered that the plastic elbow on the side of the cmc where the fluid come in through the rubber tube, had started to lift up and out of the cmc body. the plastic elbow is attached to the cmc with a small roll pin that passes through, and theres a black rubber washer that acts as a sealing ring going into the cmc. that plastic elbow had egged out around the roll pin, causing it to lift and create a gap btwn the plastic elbow and cmc body. The gap was just enough to cause air to get sucked in during pedal operation, and for tiny amounts of fluid to leak out. I bought a new cmc and i could see by comparing them how the failure of that plastic elbow around the roll pin, lead to it lifting up and creating a point leaking and air suction. I still dont know what caused that elbow to egg out, but replacing the whole cmc fixed the issue. it could have something to do with the act hdss clutch or the steel braided line going to the slave, being to heavy on the cmc leading to its failure, idk. I will mention that bleeding the cmc and slave took forever. theres no great way to bench bleed a new cmc on the evo, and the location of the bleeder screw on the slave isnt ideal. ive found that once air stops coming out the bleeder, its best to give it a couple more cycles or pump hold open, just to be sure. All you can do is keep bleeding until its good. even if it seems like its not working, eventually itll start building pressure. I recommend also doing the caliper bleed first, finishing with the clutch bleed. I really hate how that system is designed to share fluid. why not have a remote reservior like every other hydraulic clutch vehicle. they couldve at least partitioned the reservior so if the clutch system fails and leaks fluid, the brakes wont go next. not to mention, they made the pickup point to high. it shouldve been at the very bottom so it can nvr become exposed and suck air if fluid is low. Dont get me started on the oem plastic cmc either.

 

If your clutch line was losing this much fluid, you'd already not be able to shift gears. Takes a tiny gap to replace fluid in the line with air.

 

If you are looking for a strong and reliable replacement for your clutch cylinder, Magnus motorsports offers an upgrade for the evo X.