question about brakes...

[twastheglow]

I definately need some help here guys. And I apologize in advance for this being so long. I own a 1993 240sx and a while back I installed Z32 calipers with steel braided brake lines to the front of my car. This was probably the beginning of last summer. Since the installation, I have had a brake pedal that literally 50% of the time felt firm and stopped the car high on the pedal and felt GREAT! The other 50% of the time the pedal would go almost to the floor and would start to slow the car. If I lift off of the pedal and pushed again it would firm up and work correctly again. Almost like it had to be pumped. Needless to say it wasn't the safest. After the installation obviously all the brakes were bled per FSM. After taking it for a drive and feeling how they were acting, I took the car back to the driveway and bled them again. That still didn't fix the problem. A couple weeks later after the new brakes set in a little, I re-bled them. Still no change. Then I broke down and actually took it ot a brake shop and had them bleed them too. That fixed the problem for about 10 minutes then they went back to being 50% of the time good, 50% bad. After talking to a number of people and asking around, it was recommended I buy a Z32 BMC and an ABS (double bubble) brake booster. (I do not have ABS) I thought maybe one of those 2 parts had gone bad. I finally got around to installing everything today. After the install, my friend and I bled the brakes for a good 30-45 minutes. After leaving his house the brakes were still quite spongy but were consistant so I didn't mind. As the night went on, the brakes firmed up and now were quite stiff and touchy (the way I wanted them). So I natually thought...problem solved. HOWEVER...now my f*cking e-brake light is on no matter how many times I've tried to apply it and disengage it to try to get it to release. Also, upon starting the car after it sat for about 2 hours, the brakes went back to being sh*tty all over again. After about 10 minutes of driving, they firmed up again. My questions are...

1) has anyone ever had a similar problem?
2) would it matter if I used an ABS booster on a car that does not have ABS?
3) why would this affect the parking brake and how can I fix it?
4) do you think I still have air in the lines making the pedal feel soft for a while?

Any help would be GREATLY appreciated. I'm quite frustrated at this point needless to say.
*mike*

[Erik]

I had the same problem withthe Ebrake...except all i did was disconnect the battery for some other reason and it corrected the problem. This worked for 2 cars for me. I dont know if its coincidental but maybe that would work for you. As for the rest, i do not know.

[twastheglow]

Thanks for the advice, but unfortunately it didn't work.
*mike*

[super moose]

did you check the calipers? possibly bad seals causing the piston not to retract? also possibly an issue of knockback, which usually happens during cornering.

[twastheglow]

did you check the calipers? possibly bad seals causing the piston not to retract? also possibly an issue of knockback, which usually happens during cornering.

I'm assuming by "check the calipers" you mean the Z32 calipers. If so, no. I never checked anything before I put them on. I would assume that if the seals were bad it would be a consistant thing instead of so intermiten. But I guess at this point, anything's possible. How can I go about checking that? But why did my brakes feel EXCELLENT all day until it was parked for a period of time then it took a couple minutes of driving to get the pedal firm again? That also still doesn't answer why my e-brake is all ****ed up now too. I'm not familiar with "knockback". Cornering has no effect on my problem.
*mike*

[Wiisass]

Sounds like there is a leak somewhere. Check all the lines/fittings from the master cylinder to all the calipers, front and rear.

The e-brake light comes on when the brake fluid is low, so check that and if that's the problem, then you're losing fluid somewhere. If that's not why it's on, then it has something to do with the wire connection at the base of the e-brake.

[twastheglow]

I'm certainly not losing fluid. I just checked the MC and it's full. So that means, there's no leak, and the e-brake light isn't on because of low fluid. Thanks though. :cry:
*mike*

[twastheglow]

***UPDATE***
I tried driving the car today to run some errands. At first the pedal felt soft but still stopped the car fine. After about 10 minutes it tightened up and became firm again. Then my e-brake light went off by itself. Then within a minute of that happening, I could feel the rear brakesslowly being applied more and more until I had to really get on it just to keep the car moving. As soon as I let off the car would come to a stop. Now it's parked and I'm going to put the stock MBC back on it and try to rebleed everything again but much better this time. Since all the fluid obviously leaked out of the removed stock unit that I took out yesterday, can anyone explain to me step by step how to bench bleed the unit before putting it back in? Thanks again.
*mike*

[[sr20]sean]

when you bought the calipers did you rebuild them first?
what do you mean by bench bleed the system?

[remety]

Just get a friend and bleed the whole brake system. Best way to do it. If the problem is still there start to look futher. Try to rule out as much as possible.

[JKrome]

my **** did the same thing when the MC went bad...