Spongy Brakes and Low Fluid in VW Fox Needs Diagnosis

I experienced similar symptoms with my 2008 VW Polo TDI at 155000km. The spongy brake pedal and inconsistent pressure are classic signs of either air in the brake system or a failing master cylinder. In my case, the master cylinder was leaking internally, causing the brake fluid level to drop gradually. The warning light came on intermittently. After inspection, the mechanic found that brake fluid was seeping past the seals inside the master cylinder. The complete repair required: Master cylinder replacement, Full brake fluid replacement, Bleeding the entire brake system This is a serious safety issue that needs immediate attention. A spongy brake pedal means the brake system is not functioning at full capacity, which could lead to brake failure. The low brake fluid level you noticed is a critical warning sign. The symptoms you describe match exactly what happens when air enters the brake system or when the master cylinder starts failing. Since you already had it checked without resolution, focus on getting these specific components inspected at your next shop visit. Time at the shop: Full day job Severity: High priority repair

Thanks for sharing your experience with the master cylinder issue. That matches what mine turned out to be too. The mechanic discovered multiple problems with the hydraulic brakes once they did a proper brake inspection. The repair included replacing both the master cylinder and some corroded brake lines. The warning light kept coming on even after the first fix attempt, which is what made them check the lines too. Did you end up having any other related issues pop up afterwards? And if you dont mind sharing, what was your total repair cost? Just want to compare since prices seem to vary quite a bit for this type of work.

Glad I could help identify the issue. Since my master cylinder repair was completed, I havent experienced any more brake system problems. The brake fluid level has remained stable and the warning light hasnt returned. The spongy pedal feel is completely gone, giving me back that firm brake response. My total repair costs came to 480€, which covered the master cylinder replacement, new brake fluid, and the complete system bleeding. This was actually a fair price considering the amount of labor involved in ensuring the entire brake system was properly serviced. Just make sure to keep an eye on your brake fluid levels during your regular maintenance checks. A properly fixed brake system shouldnt need frequent fluid top-ups. If you notice the fluid dropping again, get it checked immediately since this could indicate other brake components need attention.

Thanks for the cost breakdown. My repair ended up being more expensive at 680€ since they had to replace those corroded brake lines too. But honestly, worth every cent for working brakes. Took it to a certified brake specialist this time after that first failed repair attempt. They did a complete system inspection, replaced everything that was worn, and properly bled the brake lines. The pedal feel is solid now, no more of that scary spongy sensation when braking. The warning light finally stopped coming on and the brake fluid level has stayed steady for the past few weeks. Really relieved to have this sorted properly. Going to stick with this new shop for future brake work since they actually took the time to find all the issues instead of just doing a quick fix.