G'day all,

I am encountering a problem where occasionally my brakes decide to play dead. Where they go spongy, but hold pressure after a few pumps. After researching I have found that the fix is to trigger an ABS event to a complete stop, and in my cases this has fixed it. This problem has happened twice, both times during wet weather, so I am presuming that that is the cause of the problem. My question is why does this happen, and is there a more permanent fix?

 

I have been having the same issue on my 2008 i Touring.

Second time this issue has happened in 2019 calendar year. The first time the brakes went soft my shop was able to reset the ABS Module and the brakes went back to normal.

A couple days ago, I went over a large pothole with my foot on the brake and the brake went soft again. Very standard and well-documented problem: brake engages normally at the beginning, goes soft in the middle, and does engage again towards the bottom, coming to a complete stop relatively predictably each time.

This week when I took my car in, the same shop suggested an expensive Master Cylinder replacement, however I am not convinced this will fix the problem due to dozens of similar reports from Mazda 3 owners who say the problem remained after a MC replacement.

Any suggestions or updates on this issue are appreciated. I could drive about 40 minutes to find an empty gravel road to engage the ABS system but would rather find a more permanent solution. My gut tells me that the entire ABS Module will need to be replaced at some point which is an expensive repair.

 

@ 2008Owner,

I have spoken to people and further diagnosed the problem as triggering the ABS no longer fixes the problem for me. The problem is with the ABS pump and can be explained in this video.

You Tube

. It seems quite common, but it's interesting how so little mechanics recognise the issue.

I am yet to get it fixed, as it is indeed costly. A mechanic I heard from says that it is a common occurrence and gave a rough quote of $550 AUD, replacing the pump with a second hand one, from a scrapper.
As for the options ...
1) Mazda quoted me $5500 for a new pump, or other warehouses can charge between $600-800 AUD for a new unit.|
2) There are places which refurbish your pump for about $300, but for me, there are none in my city, meaning I will have to send it away and be weeks without a car.
3) I will most likely just get a used part from a scrap yard for around $100-150 and hope that it doesn't break again. The mechanic said that all the replacements he has done, he has never had anyone return with that issue.

The final straw for me also was braking over a pothole, interestingly enough.

 

I appreciate the response - I have come to the same conclusion in my independent research and have seen some of these videos which line up. I have been recommended a MC replacement by a second shop but am yet to receive a compelling reason why other than "that's the only other explanation" due to my brakes being in good condition, no leaks, no external MC leak, and no ABS codes on the computer. It's frustrating and I do not want to spend $500 on an MC replacement when I can almost rule that out. It just doesn't make sense, but trial and error seems to be how these shops operate when they can't physically inspect the parts.

I understand the processes that these shops operate on, I just thought that someone one would have seen this issue before and could identify the problem with confidence when it seems to be so well-documented. I will check back soon as to how this develops. Car owners need a more commonly understood explanation.