99 5sfe - weird brake vibration and engine vibration

[RahX]

Sounds like you might have a bad brake hose or caliper or both. Try jacking up the front end and having someone in the driver seat hit the brakes and let up and you try to turn the wheel. If the wheel is hard to turn then gets slightly easier, open the bleeder and see if it gets any easier. If it DOES you have a bad brake hose. Servicing a caliper is not recommended if you don't know what you're doing, they're pretty easy to mess up and i'm not sure they sell rebuild kits. A lot of times the bore that the caliper piston sits in gets corroded over the course of years and there isn't much you can do about that short of replacing it.

[zorobabel]

Thank you very much usedranger, you sure took a lot of time helping . I ended up with the Permatex 24115 silicone formula, the one I linked.
I managed to take out the piston by connecting it back to the brake hose and pushing it out. No corrosion at all, nothing wrong with it, as far as I'm concerned. I cleaned it up and reassembled it, mounted everythig back on the car ... and surprise ... no change
I'll check the brake hose next as RahX suggested.

[Mike Gerber]

"mounted everythig back on the car ... and surprise ... no change"

There will not be any change if the rotor is warped, until that rotor is resurfaced or replaced. Did you check and/or relube the slide pins on that caliper?

Mike

[usedranger]

You said there are issues with your landlord prohibiting working on the car, but as MikeG and others have said you need to get the rotors trued up. Either take yours in and have them turned or get a new set [make sure the store tests those to make sure that the new ones are ok. Then reassemble BOTH sides, {replace both sets of pads, clean and lube slides etc}. If your brakes are working properly then you can begin to tackle the "vibrations... and shuddering" that you have mentioned, which may turn out to be an entirely separarte problem from your brakes. Also, have you checked for any leaking at the Master Cylinder, or booste?.

As suggested in a past response, Wheel balance may be a good start although there is a cost to that. Start by looking to see if the weight has fallen off one of the wheels (no costthere and even the landlord can't object to that.!

Then get a buddy to start the engine and you poke your head under the hood;watch to see if the engine moves if he has his foot on the brake and puts it in gear. Use something like a board or rod as a fixed reference point front - back, side-side. Good luck.

[zorobabel]

Ok, here's another update on the matter. I changed the rotor about 2 weeks ago and nothing changed. I also realised that after the wheel gets hots and starts vibrating (which now happens regularly after 30 min on the streets and sooner on the freeway), I must unscrew the bleeder plug on that wheel. Once I start doing it, brake fluid rushes out in a small jet. Then I'm good for another 30 min ).
So I assume you all agree that it's the brake hose or brake line. I tried to get them off but I'm having a real hard time with those cheap alloy 10 mm fittings, they start to round when using a wrench on them. Any suggestions, on how I could unscrew them for inspection?
Another thing: I followed the brake lines, and the front driver brake line is short and connects to a 3 way manifold right next to the master cylinder. The front passenger brake line connects to a manifold towards the middle of the engine compartment. This is a 5 way manifold with one line going directly to the brake cylinder and a second one going to that first 3 way manifold; I assume the remainig 2 lines go to the rear wheels. It doesn't look like such a smart system, I believe it has more pressure on the front driver brake line even when working properly.

Thanks again for the help.

[jdmccright]

Sounds like there may be an obstruction in the brake line. Loosen the "banjo" bolt using a box-end wrench or a 6-point socket wrench. If worse turns to worst, douse it with pentrant, and use some vise grips on it.

Now that I think about it, the obstruction may be that rusted banjo bolt itself. If that is the case, then your probably going to end up buying a new caliper and brake hose...about $40 total. No need to fight that bolt, just unbolt the caliper and disconnect the hose from the brake line. Replace and relube all the sliding pieces.

Get the rotors turned to true them up. Any warpage from the bad caliper will remain. The landlord will have to suffer a few hours of a car w/o wheels. Just be sure that you use drip pans to catch any fluids.

I'll throw the note in that Toyota uses sliding pins that have rubber rings around the ends to help with centering them in the caliper holes. Over time they can swell up and prevent the caliper from sliding freely. Auto parts stores don't sell them and they don't come with newly bought pins. For just a few extra bucks (seriously), buy new pins with the rubber ends from the dealer.

Reinstall the rotors, caliper & hose and scuff the pads to prepare them to accept the new rotor surfaces. Finally, flush that brake fluid with new fluid to get rid of the absorbed water. I'd say to replace the other caliper and hose, too, since it is likely affected as well. But you could save it for another sunny day knowing it needs to be done in the near future.

Good luck!

[Mike Gerber]

That rubber brake hose may be collapsing internally and not allowing the brake fluid to flow back away from the caliper. This would mean the caliper would always be putting some pressure on the pads and hench the rotor. After a period of time the rotor warps from the heat it is experiencing. I have to agree with jdmccright. It's time to replace the caliper and brake hose on that side.

Mike

[zorobabel]

I changed the brake hose and nothing changed. Damn it! I used a flare nut wrench and after many tries, I was able to finally loosen the fasteners, the one next to the brake hose was a PIA. Is the banjo bolt the one that connects the brake hose to the caliper? If positive, that one was no sweat with a 14 mm 1/2 in socket and a breaker bar, I loosened it previously when I took the caliper apart.

Could some one please check their 99 Camry CE, no ABS, US model for similarity with the brake line setup in my previous post? Thanks.

I was able to run a wire through the 3 way manifold and through the brake line segment that connects the master cylinder to that 3 way manifold (it connects to the first piston, the one next to the brake booster), so they're off the hook.
The brake line segment between the brake hose and the 3 way manifold is rather long and I couldn't run the wire wire through, but it went in a little bit more than halfway from either end. I'll have to mess more with that one.
I assume that with a faulty master cylinder I'd get pressure in the passenger caliper too, right? I did some reading on how stuff works, and the previously described brake line arrangement is weird, I doesn't have 2 circuits.

Thanks for helping, posting and reading!

[jdmccright]

I'll repeat what's been said but haven't heard you do yet...get the rotors turned to eliminate any warpage and either re-lube the slide pins or get new ones. If the pins don't go in & out easily when greased, get new ones. Also, see my note above abt the rubber rings on them.

A pump or two of the brakes with the bleeder open would prove or disprove a blockage in the system upstream of the brake hose.

You mention having trouble getting a caliper piston out to inspect it. It should come out easily with a pump of the brakes or compressed air. The caliper surfaces can look fine but if the piston is cocked in the caliper bore it will hang up and not retract...usually due to uneven caliper wear or misaligned pads due to rust formation.

[zorobabel]

Better late than never, but I have to tell you I fixed the brake pressure issue. It's been 3 months already, but at least I had time to make sure it works.
It wasn't the rotor, caliper, brake hose or brake line - IT WAS THE MASTER CYLINDER. What exactly was it inside of it I don't know, I don't feel like taking apart that SOB, I just replaced it.
I guess it only affected the front driver's side caliper because of the bad design of the brake line circuit (as I mentioned in an earlier post). If I had more confidence in this car over the long term, I'd redo the circuit to a more conventional/simple layout.
Thanks to all of you posters for bearing with me!

[Brian R.]

Thank you for the feedback on the problem.