I know alot of you dont know me , but I was on this site along time ago and tho I no longer have a z im looking for another one here shortly and i have a good deal of auto knowledge but im stuck and need help ( if this isnt the right place to post please move) My dd is a 91 dodge d150 2wd with a 3.9l v6. I have replaced the master cylinder, one caliper that was stuck and both rear wheel cylinders and bled the brakes countless times. Now the problem is i have no brake power. When the engine is off the pedals are stiff and dont go to the floor … As soon as i turn the key on they go to the floor. Some times it takes about 3-4 blocks for me to loose all brake pressure. IS it just air in the lines i cant get out or is it the power booster?
I’d say the power booster. If it was air in the lines then you wouldn’t be getting a hard pedal with the engine off.
I don’t know for sure though.
Did you bleed the master cylinder right? If not you could get bubbles. Also your brake booster might be going out. Check vaccum lines as well too around there. But my guessing is that the whole unit will need to be replaced and bleed well. There is a different procedure for bleeding master cylinders. If you need help just pm me
yeah i bench bled the master cylinder, replaced the vacuum booster and still having problems… taking it to a shop in the morning cuz im frustrated