So last week I suffered from a sudden loss of pressure in the brade pedal. I decided to a complete brake service and have did the following: Upgrade front rotors to TT OEM's. Upgrade front calipers to TT OEM's. Replaced the new pads from my NA Calipers (still really meaty). Bleed all four brake lines. Complete brake fluid flush. After completing all of that I went for a test drive and the pedal is still rather long. There just doesn't seem to be much pressure. Its fine while standing and when bleeding the pressure was fantastic. Only when driving it goes away. We re-bled the brakes and tried again and not much change. Any thoughts. I'll probably just take it to a mechanic on monday to get a complete brake fluid flush and get them to give it a once over. If you have any idea's what else could be done or what is going on would love to hear it! Cheers Paul
Did you bleed the abs actuator, and follow the procedure set out in the manual. Also check the vac line from the balance tube to the booster.
If you lose pressure, you have a leak so air got into the system. If you don't lose any fluid, the leak is most likely in the master. Changing the rotors is of course not going to fix the leak and bleeding the system would at best only temporary fix the problem. What is important is not what the brakes are like after your bleeding attemps, but the fact you suddenly lost pressure. Find and fix that first.
Be VERY careful bleeding the ABS Paul, done wrong the fluid shooting out of the ABS will cut you in half! If you left the brakes the way you did on Friday then I would surmise air has travelled to the ABS and is sitting in there. Make sure you follow procedure and have the car running when bleeding the ABS. Also have a towel around the unit to soak any spillage. Brake fluid is nasty stuff.
Well fingers crossed its the ABS. Rob's on his way round now with a bleed kit and we'll give it a shot. If not.....looks like its the master cylinder. sigh.
Just completely bled the ABS. Went through about a litre of brake fluid to make sure that the system was completely flushed. Colour is good and it appeared that all the air was out of the system. However, take it for a drive and still the pedal is long. Now granted, its more pressurized and I can feel the abs kicking in when I slam it down, it still takes the majority length of the pedal before the brakes completely grab. So what are peoples thoughts now. Either the MBC needs to be fixed or there is a big air pocket somewhere in the system. Will be going to a brake workshop tomorrow to get it professionally looked at, but just wanted some thoughts on what I should get them to diagnose first. Cheers boys!
They are going to suggest you let them re-bleed it and then they are going to want to check the M/Cyl. Master Cylinder overhaul (S/Steel sleeve into yours, assuming it hasn't been done before), will cost about $250
Yeah thanks greg. Figured that would be the case. Just gonna get a basic full system bleed done. Then if the issue persists I'll get them to look at the m/cyl.
