Ok I tried to figure this one out by myself. But now I am getting stumped and asking for suggestions. As many of you may know from my other thread, I bought this abused 06 HHR LT with a jumped timing chain, I have zero information on any previous work that was done to it. I did get the engine back together and running good. Now,,,,

the brake pedal goes all the way down, about an inch from hitting the floorboard. However, it is very consistent. It stops the car just fine, and always goes down the same distance. One thing to note, I can “feel” the pedal travel the full first chamber of the master cylinder, then the brief space between, then I can feel it enter the second chamber of the master cylinder. If memory serves me correct, one chamber is for the fronts and the other chamber is for the rears. I hope this makes sense. In normal braking with a good pedal, you would never feel this and the pedal will only travel perhaps an inch. This one travels about 3.

What I’ve done.

1. Checked the master cylinder level, it was full.
2. Pulled all 4 tires and inspected all brakes. Could not see any visible leaks, moisture or rusted/broken brake lines.
3. Adjusted the rear brakes. They were way out of adjustment. One side much more so than the other. It looks like someone recently put shoes on, one of the drums is lightly gouged. You can tell they hit metal and never turned or replaced the drum. The drums are now lightly snug with the shoes
4. Gravity bled the brakes. I did notice a couple bubbles come out of the front calipers right when I initially started. But this made no change to my problem.
5. Re bled the brakes, this time with the help of my #2 pumping the pedal. All 4 bled, no change however. Never saw any more air come out.

Observations:
The last time I bled them, although there was no change to the distance of the pedal, the ABS light no longer comes on. Fluke perhaps?

When my helper pumped the brake pedal I could hear the idle of the motor fluctuate wildly from the vacuum of the booster as she pumped the pedal. I am not sure if this is normal or not.

I suspect a bad master cylinder. A neighbor disagrees and says its for sure got air in it. I have a tendency to believe him, except I see no leakage and I cant bleed any air out.

I am open to suggestions. However, I will not be back home to try anything until Thursday so my speediness to reply here may suffer. Such the life of a truck driver

Do these HHR’s have any known issues with the brake systems or is this just brake o problems 101?

 

Sounds like the booster to me. It is not normal for stepping on the brake to change the idle. If it does it means air is getting sucked through the booster..

To test the booste:
engine off
pump the brakes until the pedal is hard
while holding pressure on the pedal start the engine
the pedal should then go down if not it is bad.

 

That’s what I was thinking donbrew. It will be my very next test Thursday morning

 

It might just be the booster check valve, but I’d have a look at the booster vacuum hose at the intake manifold, is it loose and leaking there? Is that nipple broken off or cracked at the manifold?

 

Quote: "4. Gravity bled the brakes. I did notice a couple bubbles come out of the front calipers right when I initially started"

Never heard of trying to gravity bleed a hydraulic brake system. That probably allowed air into the system.
If you have ABS on this car you'll most likely need a pressure bleeder to get any air out.

 

You can gravity bleed a system. It will take sometime though.
Doing this way will not allow air in the system unless you drain the master.
I will agree a more positive way to bleed system (and faster) is a pressure bleeder.

 

TruckerKevin
Besides what Don has suggested also start and run the engine for a minute or so.
Shut off and pull the vacuum hose off of the booster, you should hear air rushing into it.
To check for a bad master cylinder, with the engine off, hold light pressure on the pedal and see if the pedal goes to the floor.

 

Cat Man HHR

Just got home from the big road. While I have yet to test the brake booster, I did the test with the key off engine off, my brake pedal does indeed go down far. I can pump it up and it briefly stays up, but sinks down far.

So we are looking at a bad master cylinder? Cool

 

A rebuilt MC is cheap, if you gotta R&R it to get to the booster, might as well.

 

Yes Donbrew if I have to replace the brake booster I will replace the M/C for sure. I am going to go out there in a while and run the test you told me to try here soon. But I am thinking the master cylinder is for sure bad.