My old skyline (temporary non- toyota transport ) has rear drum brakes. When the car is not running the rear brakes work beautifully, heaps of presure etc. But as soon as the engine is started there is nothing in the rear, it doesnt even move the slave cylinders 1mm?? the master cylinder has just been reconditioned yesterday , (i took it to a different shop today to be re-tested, it is perfect), so is my booster the problem? the front brakes work great in both conditions. Any help would be great,
cheers,
chris