I haven't gone back through the entire posts, so forgive me for asking if you've already done this. Have you tried replacing the caliper guide pins on that rear brake? Maybe one of them has a flat spot worn on it and it's just not letting the caliper fully release from time to time. Did you lube them really good before putting it back together? I'm glad it's not my car, because it's driving me nuts too! LOL

 

Hahahaha! I did lube the death out of it. And a visual inspection showed nothing unusual. No rust either. But all I've done has helped tremendously. I'm busy driving it until the wheel falls off. Lol

 

All I can say is good luck with it. Unless you have the time and money to go through and replace everything in the entire brake system, including the proportioning valve, I'd say just drive it like it is.

 

I know. I hate to be that guy. Changed everything but layer find out it was air in the line. Lol. But I think I nailed it so I will update you guys. The car has been running really good and only got 1 hard padel they the week. Not bad since I was getting it daily. So yesterday I rerouted the booster hose like it should have been prior to me inspecting it. I did pop out the valve and grommet. Blew and sucked and it works fine. Put it bad and routed the booster hose. Drove all day and the pattern is back. 20 minutes into stop and go traffic the pedal gies hard and brakes drag. Lol. So im changing the valve and grommet soon. HAS TO BE THAT!

 

Man, that's going to be a real bitch if you discover that the check valve was bad and you did all of that other work. I'm not saying it was for nothing. You've basically redone the brake system and I'd call that preventative maintenance. Let us know what happens.

 

Hey rube. Problem solved. I posted this on another forum.

["But I'm confident I found the problem! I suspect either the booster check valve or the factory clamp on it. Why? Last week I took it off to visually inspect it. Nothing looked bad. At the time I didn't know how to check it. So I just put it back and the problem went completely away for the whole week. I figured a small vacuum leak on the factory clamp. Remember that Rube? So, 3 days ago I found out how to check the valve. Blow and suck. In which it did exactly that. So I put it back and drove the car. 20 minutes later the exact same problem came back. After a full week of flawless operating. So I said "bingo". Touching it make the problem return. So I simply readjusted the factory clamp a little and turned the grommet just a little to see if it had a effect. Guess what! For the part 3 days it hasn't done it! To is either the factory clamp isn't gripping properly or the grommet is a bit warped. So I'm going to just buy a new check valve that comes with the new grommet since it's super cheap. 9 $. And that's should eliminate the issue. Thanks for all the feed back! Luckily I didn't spend on replacing the caliper and all the lines! So everyone remember this!"]


So luckily I only went - 38 $ in tracing this issue. Thats from PS brake line in which showed the highest wheel temp. The front brakes were done about 2 to 3 months ago since they were below 10%. In which I thought that it could possible eliminated the issue. Problem went away for about 3 days. I thought, awesome! But it came back on the 4th day. But now that I think about it, I did move the booster house a little when I was filling the brake reservoir for a simple bleed. That must have been the temporary cure I experienced. Fast forward 3 months later, I got concerned since the intermittent hard pedal and dragging were a daily thing. That's when I said let's just look at the rear brakes completely. That's when I discovered one pad that was 50% less than the rest. In total being about at 10% left of its usage. I figured might as well throw in new pads since they are close. So luckily all the work was needed but the 38 $ front brake line. So remember this!

 

Hope the valve lays this problem to rest, but I'd still be concerned about that caliper/guide pin if the wear was that grossly uneven.

 

Ok. Put in the new factory booster valve and gromet. Nope. The the problem. Lololol. So now I'm suspecting I did the bleeding procedure wrong and may have air in the system. Do you guys know what type of abs it has? Is it alphi7? And what's the proper bleeding procedure? I did the RR RL FR FL old school method. It worked and got good brake pressure, but maybe air is expanding with heat?

 

Here is another hint I noticed. Brakes dragged. I open the good and unplug the booster valve. I hear a healthy vacuum hiss, immediately the car rolls back. So when the vacuum gets removed the brakes let go. Hmmm. Either the booster is the problem or I might be close in my theory of air expanding. What do you guys think?

 

I don't think it's air expanding. You only have a certain volume available in the brake lines. How in the world could any air in there expand? I'm no physicist nor a mechanic, but I just don't see how that's possible. Hell, you've replaced everything except the booster. Why not go ahead and replace that too, if you can find one at a reasonable price?