Brakes? Who needs 'em?

It turns out, that the world's most boring car becomes slightly more interesting if you remove all feel from the brake pedal.  My 2000 Camry (beige, 4 cylinder, automatic, tan interior...  see I told you it was the most boring car in the world) has been giving me fits.  I've put in a new master cylinder, bled the brakes several times, and had a shop that I trust adjust the rear drums and bleed the system, and the pedal is still soft.  I'm going to put this in bullet points so it is easier to read:

• Brakes are still as powerful as they have ever been, but they require more pedal travel than they used to, and they give no feedback at all.
• Engine off, pedal is firm at the top of its travel.  Start the car, and the pedal drops and is soft.
• Brakes cannot really be pumped to firm them up.
• Once the brakes are really applied, the pedal does not continue to drop.  It is not at the end of its travel.
• No fluid loss.

Based on these points, think the air is out of the system and the master cylinder is fine.  The shop suggested a new master cylinder, but I'm not convinced that's a good diagnosis.

Can rubber lines degrade but still be functional, or do they typically fail by rupturing or failed fittings?  I have a feeling that the rubber lines in the car are flexing a lot while braking, which is causing the problem.  I've never encountered this problem before, and I'd love to hear what you kind folks think before I spend any money and spill brake fluid all over my garage floor again.

Help make the Camry boring again.

sounds like the vacuum booster has taken a E36 M3, but let me ask a couple questions before i hang my hat on that internet diagnosis.

you say the pedal takes more travel to stop the car.   does it also take more force?

you also say they are still as powerful as they have ever been.  for that reason i'd agree with you that the MC is not the problem.

what problem were you trying to address when you installed the new MC?

I think you are right that the rubber hoses are the problem here. 

All the components are stock-sized, right?  No calipers or master cylinders with larger bores?

If it's not hoses or a mis-sized hydraulic part, it could be poor adjustment on the brake pedal actuator rod (the part that pushes on the MC's piston), that's a nasty problem with similar symptoms.

Did you replace the MC specifically because of this issue? Does it have ABS?  If it were a brake hose, it would probably pull to one side under heavy braking, but I agree that is a good thing to look for.  

I'm going with air in the lines as it is the most likely scenario.  I'd take a second look at that MC to validate it is the correct one for the car.  Rockauto lists different MC depending on with or w/o ABS and Traction control.  

First thing I thought of was air in the lines.

Let's see if I can get all these questions at once...

Pedal does not require more force to achieve same braking force as before.  In my head, this rules out a faulty booster.  Is that accurate?

MC replacement was to address creeping pedal, especially noticeable at stop lights.  It did fix that problem.

The car has ABS.  The system sucks, but it is present and "functional".

All components are stock sizes.  MC is the correct one for an ABS car.  The bore is the same from the ABS and non-ABS cars - I haven't measured this, just trusting the details on RockAuto.

Brake pedal actuator rod is a new one to me.  If it is like a clutch pedal actuator, it should be easy enough to adjust, but the pedal is firm at the top when the car is off.  If it is set short, shouldn't the pedal rest on it since there is no hydraulic pressure causing it to return, or is there typically a spring to assist pedal return?

I'm still leaning toward rubber lines, but I'll give this some more time to see what else people think.

I don't think it is air in the lines because I cannot pump the brakes to firm them up.  I was really hoping it was the problem, but I was sick of bleeding them, so I took it to the shop.  They used a vacuum system of some kind and the problem is still present.  I could definitely be wrong, but I'm not quite convinced yet.

Your description in your first post sounds almost normal.

 What am I missing ?

Scary lack of pedal feel.  Excessive pedal travel.  Brakes still work, but you never really believe they are going to do their job.  I've put almost 100,000 miles on this car, so I know these brakes are never going to be amazing, but they are definitely not normal right now.

Edit:  I just reread the first post.  It does sort of sound normal by that description.  Definitely not normal though.  It's bad enough that I'm hesitant to let anyone else drive it.

SWMBO had an 02 Camry and it did the same thing since new. I never did like the feel of the brakes but they always worked. You say it's always been like that? Sounds about normal to me comparing to another Camry.

wlkelley3 said:

SWMBO had an 02 Camry and it did the same thing since new. I never did like the feel of the brakes but they always worked. You say it's always been like that? Sounds about normal to me comparing to another Camry.

It is much worse than it used to be.  Originally it was boring, uninspiring, and safe.  Now it is unnerving and borderline unsafe.

I edited the first post a little to hopefully be more clear.

bigeyedfish said:

I don't think it is air in the lines because I cannot pump the brakes to firm them up.  I was really hoping it was the problem, but I was sick of bleeding them, so I took it to the shop.  They used a vacuum system of some kind and the problem is still present.  I could definitely be wrong, but I'm not quite convinced yet.

Did the shop cycle the abs module when bleeding?

You may want to try finding a dirt lot/road and making a few stops that engage the abs. See if the pedal feel changes after that, which could indicate air trapped in the ABS unit. 

You may have a seized slide pin on a front caliper.  One seizes, you step on the pedal, the caliper mount flexes to allow the pads to contact the rotor, let off the pedal, the caliper flexes back to its original position.  Gets worse as the pad wears to a taper.

Pedal does not require more force to achieve same braking force as before.  In my head, this rules out a faulty booster.  Is that accurate?

 Yes, but more to the point, the booster can't fail in a way that makes the brakes softer, only harder.

If you want to inspect the hoses for swelling, just have someone else repeatedly jamming the pedal with all their might while you lay eyes on the hoses. 

In reply to No Time :

Long gravel driveway and the roads are covered in ice right now.  Much ABS activation.  No change.

Sounds like the next step is pulling the front wheels and watching the calipers and lines while someone else is applying the brakes.

If a pin is seized enough to cause a soft pedal, the pad will be worn on an angle.  Look close for that, too.  Ganerally, its pretty easy to give the bolts a spin to see whether the pins are seized.

What do you need brakes for? All they do is slow you down...

Step one to me, do you have an IR temp gun?  (you can get them for like $20 at harbor Freight)

After some brake heavy driving, get out right away and get temps from each corner. Suggest doing twice, once walking around clockwise, once counter-clockwise. 

Are the left and right hand side temps close for each axle?

I diagnosed bad softlines that way, but mine seized the brakes ON. 

at the very least, it will tell you if a problem is isolated to one corner rather than a system-wide thing.

Some cars need the abs to be cycled while bleeding.  If you shop used a vacuum bleeder only this is probably the issue.  This happens to me once on a 2001 Ford Explorer.

rdcyclist said:

What do you need brakes for? All they do is slow you down...

Also you pay 30 45 dollars for a tank of gas, that is to make a car go,once you use the brakes. Just wasted that money 

Okay, another question or two.  If there is air in the ABS module, can you typically pump the brakes to get the pedal to firm up?  I think I'm just going to throw some new lines on it and bleed the system again.  They've got to be cheap.  Any tips for cycling ABS while bleeding?

Drive it a while.

For some reason, new master cylinders and new calipers both seem to need to "break in".  More so calipers than masters.

Knurled. said:

Drive it a while.

 

For some reason, new master cylinders and new calipers both seem to need to "break in".  More so calipers than masters.

Can you define a while?  Not being snarky, I'm genuinely interested.  I've got some miles on it, so I don't think that's the issue but I've never heard this before.