[NickD]

Engine off, pressing on the brake pedal three times to release the reserve vacuum, reach a very hard pedal when only depressed about a half an inch.

With the engine running, the pedal goes down about an inch and a half. Never experienced this on other power brakes I have or had. With my other vehicles, doesn't make any difference with the amount of pedal depression, engine running or not. But a huge difference on the amount of pressure required to stop the vehicle with the engine off.

Supra or motorhome for example, even my daughter's Soul, that is a vehicle by the way, strange name. With the engine running, pedal only goes down about a half an inch, with very little pressure to stop the vehicle. But on my Cruze, this depression is more like an inch and a half, quite a bit more depression than other vehicles.

Is your Cruze this way? Typically a solid rod between the brake pedal and the master cylinder, even with power assist. But something in that brake booster is permitting that pedal to do down a lot farther.

If I switch the engine off while coasting in neutral, then get only a half inch of depression, but sure have to step on it hard to stop this Cruze. But only a half an inch.

 

[brian v]

Yeah I kinda noticed that a long time ago that there is extra play in the pressure test on the brake peddle while running and not so much while the engine was off ..Maybe there is an bigger vaccum pressure when running that allows this added travel before the brakes start to thrust into a locking position to slow the cruzen down from that steady pace from Red Light to Red light ..as you clearly may discern I do Like RED !

 

[72buickgs]

That brake pedal movement, as u say of 1-1.5 inches, is normal, although my wife's new 2015 Cruze LT does have more pedal movement to engage the brakes that did her 2011 Cruze LS. That extra pedal movement has in the past been done to other vehicle brake systems to save the pads and rotors, because there are too many drivers who ride the brakes.
That was done in the 1960's for police cars because officers mostly "road" the power brakes (left foot always on the brake pedal) and wore out the drums & brake shoes way too soon.

 

[Aussie]

Back in the seventies I owned a car with 4 drum brakes and when the adjustment was correct the pedal was hard right at the top. I didn't have power brakes on this car so I had a booster fitted and the pedal movement was a bit longer, but boy did the car stop better.

 

[NickD]

Beginning to sound like this is normal for the Cruze, 2004 Cavalier sure wasn't this way. Has me wondering how they are doing this, shop manual is no help. But very good in telling not to drive my Cruze over my foot. I didn't know this.

Guess the only way to find out is to take it apart and examine it.

Fords were notorious for having way over sensitive power brakes. Need a very delicate foot or will fly through the windshield.