odd problem - Toyota Nation Forum : Toyota Car and Truck Forums

sampsongrsk2010 · 08-09-2010, 10:17 AM

Ok so this may be rather lengthy but I havent slept in the past day due to traveling and am kinda hyped up on coffee, just an FYI if it looks like i am rambling...oh and I may include irrelevant information but i dont want to miss out on anything.

I am currently driving a 1998 4 cylinder camry LE with about 175k on it.

I absolutely love my car as it is so incredibly easy to work on and hopefully this is a simple problem with a simple solution....

About 2 months ago I vacuumed out my power steering fluid as it looked very burnt. In the process some of the fluid got on my front passenger side rotor. I thought nothing of it and drove my normal drive. About a day later there was a little vibration in the steering wheel and some light noise being emitted from what i pressumed was that same tire. I thought maybe the fluid created a temperature differential and caused some mild rotor warping after applying brakes at higher speeds....

Fast forward to the past week. The car now vibrates rather violently after it warms up for a few minutes. It emits a loud thumping sound after it is warmed up from travel that gets to the point of it being extremely loud. With both problems combined it seems borderline not safe to drive. Oddly enough after it is warmed up (as it does not do it at all no matter what speed when i first start driving) it does it the most from about 35mph to 65. When it gets really really warm it does it about at any speed.

I thought it was a warped rotor so I had the rotors and brake pads replaced.

After I got the rotors replaced the problem continued and appeared to become more severe. The guys that did the work for me ( i live in a condo complex and cannot do something as simple as replacing rotors without fear of the ever present condo nazis taking their wraith out on me) I dont think they cleaned the mineral oil/preservative off the rotors before putting them on as they began to smoke after I got off the freeway. As always, with the vibration and even louder thumping sound being present I did notice that the front passenger side tire
(rotor) smoked much heavier than the driver side. I presume that there is some extreme friction going on between the pad and rotor so it may not be a tire problem... The tire rim is also now covered in a black dust, none of the other tires have this, even the one with the replaced rotor.

This early morning I got into the airport and waited to see if it was really driveable to get home with (as the last incident hit its climax as I was on my way to the airport). The trip from the airport to home really didnt require any braking and the problem didnt start until i was a about half way home. This is in contrast to earlier when it started shortly after leaving my home with stop go traffic. When it did start on my way home from the airport it was very sudden and very violent. Kinda suprised me.

I hope this is something as simple as a bubbled tire, although i cant see it and there is some major rotor pad friction. Maybe just something as simple as a U-joint thats going? Maybe some bum wheel bearings?

Maybe unrelated but I leave it to the experts to decide... Now after i got the car back from the shop, the brake peddle intermittently almost travels the the floor before I feel resistance and the brakes engage. If i pump the brake real quickly it seems to return the peddle motion to its old range momentarily. This seems to be more evident when the car is warm. The master cylinder was not over or under filled and it looks just about the same as it did before i took it in. Potentially air in the lines? There was no evident overfilling of the cylinder. Do you think they may have damaged a caliper? Brake boost line is connected.... No clear vacuum leaks...

So my question is what is causing the vibration and sound. Why is it the worst when the car warms up?

Is the extreme brake peddle range due to damage from where i had it repaired? any ideas or help is GREATLY appreciated, thanks!

LittleWhiteBubble · 08-09-2010, 10:29 AM

If the peddle is going to the floor I'd say there's air in the system somewhere. A bad tire wouldn't cause brake problems though so a separating tire probably isn't the culprit. Not the only one at least. Since you already replaced the pads and rotors, unless the new rotor is bad as well, you probably have a bad passenger side caliper. If its sticking that could overheat the rotor and cause warping. If you let go of the wheel while moving does the car pull right? If you have a good alignment and its pulling that would hint towards a dragging brake. I would guess at the caliper, although I don't see why the running temperature of the car has anything to do with severity.

sampsongrsk2010 · 08-09-2010, 10:33 AM

That is the source of my confusion. It really doesnt make sense as to why it only happens when it is really warm.

It does not pull in one direction or the other when driving straight. Even with brakes applied.

sampsongrsk2010 · 08-09-2010, 10:33 AM

however when it is really bad i can feel it pulsing in the brakes

LittleWhiteBubble · 08-09-2010, 10:42 AM

I'm assuming since its a 98 you have abs? I don't know a whole lot about abs systems so hopefully someone else will chime in and tell me if this makes any sense at all, but if you feel the peddle pulsing could it be an abs issue? Maybe the power steering fluid did something to the abs sensor and is freaking the system out?

If the brake system has an air bubble somewhere, maybe that's just throwing it off. I would bleed the brakes and see if that helps any. I'm glad my car doesn't have abs, almost every vehicle I've had with abs has eventually failed. Then you get those nice annoying dash lights all the time. Are you getting any abs or brake lights on the dash?

sampsongrsk2010 · 08-09-2010, 10:44 AM

I do not believe it has abs. On a off shot here, I think abs was an option. It is a front disk rear drum setup.

No brake light issues, only the old error code about my evap that i had for the past 50k (no effect to mpg!)

LittleWhiteBubble · 08-09-2010, 10:56 AM

I would take it back to where you had the brakes replaced and tell them the pedal (which I've been spelling wrong without noticing) is going to the floor intermittently and see if they will bleed it for you for free. If you complain enough and tell them it wasn't doing it before, they should do it for you.

Mike Gerber · 08-09-2010, 01:56 PM

^ I have to agree that you may have a sticking caliper. The piston inside the caliper itself may be sticking, or the caliper slide pins may be sticking. If that is the case that caliper may be applying constant brake pressure on to one of the rotors. That rotor get's extremely hot and begins to warp from the heat, creating the pulsating you are experiencing. It would also explain the fading brake pedal; as the caliper brake pads and rotor heat up, that heat is transferred to the brake fluid on that side. The fluid can actually boil causing air bubbles that can be compressed, causing the pedal to fade. I would take it back to the shop that did the rotors, tell them what you are experiencing and ask them to inspect the car for a sticking caliper.

Mike

93celicaconv · 08-09-2010, 02:46 PM

Wait - brake fluid is not supposed to boil to cause brake fade. However, I see this car has 175,000 miles on it. Brake fluid has a very high affinity to absorb water vapor (which diminishes the boiling point of brake fluid). If the brake fluid isn't flushed and replaced every 2 years or 30,000 miles, it could have degraded enough so the absorbed water vapor could be boiling on a hot brake and causing brake pedal fade. But if the brake fluid is flushed and replaced every 2 years, 30,000 miles, I doubt this explains the soft brake pedal.

Yes, sticking caliper slides will cause the pad on the outside to remain in contact with the rotor with too much pressure, and because heat in generated on one side of the rotor (not uniformly on both surfaces of the rotor), it will warp quickly. Some Toyota calipers are known to have rusted slide pins, so this problem is all to familiar.

My vote is on a caliper that has rusted slide pins, causing friction on one side of the rotor, warping it. And if that brake fluid is still the original stuff from when the car was new, then it is very likely the water in the brake fluid is boiling, causing brake fade. You should get the brake fluid flushed and replaced with fresh fluid, if this is the case.

***LynchburgCSI*** · 08-09-2010, 04:35 PM

ABS info:

73sport · 08-09-2010, 06:22 PM

I'd bet the original issue with the ATF caused dust to stick on the rotor in such a manor as to make the pedal pulsate and/or grab. Cast iron is porous your know.

?Maybe?:
The first ATF deposit onto the caliper may have trashed the calipers dust boot. Granted, a holes and/or a missing boot could lead to caliper/piston sticking, it seems unlikely in a short time but things can happen. ATF is not compatible with brake rubber! Replace the Front Calipers as a PAIR!

Quote:

Originally Posted by me;:

IME, brakes and calipers have to be very hot for a long time before the fluid actually boils. Lets say a single caliper drags enough to prevent the car from rolling on a very slight incline. This typically doesn't have enough friction to make the heat needed to boil fluid. It will make smoke tho!
Stickage which makes the car pull to one side, or OBVIOUSLY slow a car from 30mph with no throttle applied, (but engine power can easily overcome the drag); well this will boil it over in time. Driving like this for a solid 20 to 30 mins at 50mph, you will have issues within the hour. You will also have a butt load of smoke poring from the wheel well if you slow down.

OK - so the issue now; if they didn't bleed the brakes shame on them! If they compressed the caliper forcing DIRT AND CRAP INTO THE Master Cylinder DOUBLE TRIPLE QUADRUPOLE SHAME ON THEM! (This can be fatal). However and hopefully more likely they did bleed the brakes and the car now has two issues. A sticking caliper and a bad master cylinder (MC). We've seen aged MCs fail and then be OK the next day. FAIL still equals Fail!

so to me it looks like no matter how you slice it, it needs a MC!

Its the brakes! REPLACE THE MASTER CYLINDER BEFORE IT CHANGES LIFE BY MEANS OF CATASTROPHIC FAILURE! Its worth every penny!

sampsongrsk2010 · 08-09-2010, 07:11 PM

Ok tomorrow morning I am going to have them do a full brake system check...

My guess is they forced the caliper back without bleeding, i will findout tomorrow.

Nobody thinks it has anything to do with the CV joint or anything with the axle?

sampsongrsk2010 · 08-10-2010, 11:57 AM

YOU GUYS ARE AWESOME....

Especially Mike Gerber and 93 celicaconv, you guys pretty much guessed it to a T. I just got back from dealer and they wanted to charge over 2k for all the stuff that was wrong. Instead i went to autozone bought some rebuilt parts and a new master cylinder.... It got real bad this morning on way to dealer. After i got home I looked at rotor and pads. the caliper in question has turned the brake pad white!!! no idea why, and caused some major scoring on the rotor. This totally looks like a failed caliper, the peddle motion is probably due to the water or fluid boiling in the line as it only happens when it is warmed up. I could feel the heat pouring off the rotor and the rim is just about too hot to touch!!!

Going to try to get it all done today and will post pictures of what it looks like momentarily.

Thanks again guys

!

93celicaconv · 08-10-2010, 08:16 PM

Let us know what you have once your done. And, when you replace your calipers and master cylinder, to bleed the system, you will push out all that old brake fluid and have fresh, new brake fluid in there, with no moisture in it, so you will have accomplished a brake fluid flush at the same time (except for the rear lines - and I would recommend you open those up and push new fluid through those lines as well).

Good luck!