S14 Brake Problem - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

TheBleeding · 05-28-2011, 01:30 PM

Hey. First post on the forums here. I just bought a 95 240sx about 3 months ago. Took me a year to find one in decent condition. First thing before the fun upgrades is to get her running properly. I'm currently facing some brake issues. Any advise would be extremely appreciated. Heres the story.

When I got the car the brakes were kind of spongy but worked without thinking too much into it. After about 2 months the brakes started acting funny. Whenever i get into the car the brakes work fine. After driving for a while (maybe 15 to 20 minutes)... more so with stop and go traffic and constant brake use... the pedal will start to become harder and harder until it only goes down about half an inch and takes longer to stop the car than normal. It feels pretty unreliable. After the car is shut off for at least 15 minuets or so the brakes go back to normal and the whole process repeats. Also, when driving and hitting the brakes it feels like the car is pulling hard to the right. When the pedal gets hard, sometimes I wont be able to accelerate properly. Like somethings stuck. Finally, When i accelerate to about 60-70 mph and hit the brakes the steering wheel shakes pretty bad. This might be a separate issue though.

First thing i thought was a bad brake piston. I pulled all the tires. All the brake pads were relatively new and everything was in good condition except the rear passenger side caliper. The brake pads were extremely worn and the piston wouldn't turn to go back in so I could put new pads on. Also, it wouldnt slide on the pins easily. It took me a few minutes of forcing it back and forth before it worked. Seemed liked a bad deal so I bought a new caliper yesterday and put it on. I replaced all the rear brake pads and bled the new caliper. The spongy feeling went away but the same issue is still occurring. (Not sure if the vibration of the wheel or the acceleration issue is still there. Haven't felt it.)

Next i checked the brake booster to see if that was an issue. When i pulled the connection off there was definitely pressure. I started the car with the booster connection off and their was vacuum suction.

The only thing I've done to the car is a Royal Purple oil change and a Seafoam treatment. 1 can in the gas tank. Half a can in the crank. Half a can thru the booster line (not in the booster itself of course). As a million other people have done the same way before without issues. This was about a month prior to any issues occurred.

I'm pretty stumped. I'm looking to put some 300zx calipers on the front and possibly swap the master cylinder with the 300zx one as well when money is available so I don't wanna dump a ton of cash into a new master cylinder or new front calipers if I don't need to.But that's life, so if it needs done I'll do it. Again, any help would be greatly appreciated. Thanks in advance.

05-28-2011, 01:30 PM	#1
TheBleeding Join Date: Apr 2011 Location: Pittsburgh, PA Posts: 12 Trader Rating: (0) Feedback Score: 0 reviews	S14 Brake Problem Hey. First post on the forums here. I just bought a 95 240sx about 3 months ago. Took me a year to find one in decent condition. First thing before the fun upgrades is to get her running properly. I'm currently facing some brake issues. Any advise would be extremely appreciated. Heres the story. When I got the car the brakes were kind of spongy but worked without thinking too much into it. After about 2 months the brakes started acting funny. Whenever i get into the car the brakes work fine. After driving for a while (maybe 15 to 20 minutes)... more so with stop and go traffic and constant brake use... the pedal will start to become harder and harder until it only goes down about half an inch and takes longer to stop the car than normal. It feels pretty unreliable. After the car is shut off for at least 15 minuets or so the brakes go back to normal and the whole process repeats. Also, when driving and hitting the brakes it feels like the car is pulling hard to the right. When the pedal gets hard, sometimes I wont be able to accelerate properly. Like somethings stuck. Finally, When i accelerate to about 60-70 mph and hit the brakes the steering wheel shakes pretty bad. This might be a separate issue though. First thing i thought was a bad brake piston. I pulled all the tires. All the brake pads were relatively new and everything was in good condition except the rear passenger side caliper. The brake pads were extremely worn and the piston wouldn't turn to go back in so I could put new pads on. Also, it wouldnt slide on the pins easily. It took me a few minutes of forcing it back and forth before it worked. Seemed liked a bad deal so I bought a new caliper yesterday and put it on. I replaced all the rear brake pads and bled the new caliper. The spongy feeling went away but the same issue is still occurring. (Not sure if the vibration of the wheel or the acceleration issue is still there. Haven't felt it.) Next i checked the brake booster to see if that was an issue. When i pulled the connection off there was definitely pressure. I started the car with the booster connection off and their was vacuum suction. The only thing I've done to the car is a Royal Purple oil change and a Seafoam treatment. 1 can in the gas tank. Half a can in the crank. Half a can thru the booster line (not in the booster itself of course). As a million other people have done the same way before without issues. This was about a month prior to any issues occurred. I'm pretty stumped. I'm looking to put some 300zx calipers on the front and possibly swap the master cylinder with the 300zx one as well when money is available so I don't wanna dump a ton of cash into a new master cylinder or new front calipers if I don't need to.But that's life, so if it needs done I'll do it. Again, any help would be greatly appreciated. Thanks in advance.