Did you bench bleed the master cylinder?
Check the front flexible brake lines - they may be internally rutured and are blowing up (like a balloon) when you step on the brake
Air in system? Remove and bench bleed master cylinder Bleed lines and calipers
The lines run from the master cylinder to the calipers and wheel cylinders.
sounds like you still have air in brake system ,
If you only added engine oil to the master brake cylinder reservoir, remove the master cylinder and replace it with a new one. Engine oil in the brake system will destroy all rubber parts and seals, so if the engine oil worked its way to the calipers and wheel cylinders those would have to be replaced also.
There is no procedure. The only components that need to be bled (depending on work performed) are the master cylinder, wheel cylinders and calipers.
there are two types of master cylinders 1.single cylinder 2.tendom master cylinder
Get a turkey baster to empty the master cylinder and refill with new fluid Bleed the individual wheel cylinders and calipers until new fluid runs through them Make sure master cylinder doesn't empty during procedure
Defective Master cylinder?
Check the wheel cylinders - they may be leaking and you can't see it on the outside of the wheel
While the brake lines from the master cylinder are metal through most of the car body, the lines from the body (or frame), to the wheel cylinders or brake calipers are flexible, high pressure, rubber composite tubing.
It's rare....because usually the master cylinder will allow pressure to bleed off. Not the other way around. But if you have replaced the calipers, this is the next thing I would check. I suppose it could be sticking.
This is a far reaching question that needs more clarification. There are cylinders where the pistons are located. If you have a clutch then you have a clutch master and slave cylinder. On the brakes you have a master cylinder and wheel cylinders. And the beat goes on. You need to distinguish as to which cylinder you are referring.