Brake mystery/misery

[Smellycat]

Please can someone help? I have a 318is with 328i m52 conversion. The car was running fine whilst it was on the road (over a year ago) but recently I have been trying to get it through an mot to bring the beast back to the streets and I have a serious brake problem.. The pedal hits the floor when the engine is started (it rock hard when engines off) but the brakes don't lock on and it slowly rolls to a stop. Here's the mystery.. I have changed the brake calipers, bleed nipples, brake master cylinder and brake servo in separate stages and the problem has consistently stayed exactly the same. The brakes have also been bled perfectly!



Me and my mechanic are stumped so if you know the answer please can you let me know before my wife divorces me over it ???

[bigbird76]

Sounds like brake servo or master cylinder has died to me.

Have you checked the hose going from servo to engine?

Leigh