Chevrolet Cruze Forums banner

Strange robotic sound when pressing or releasing brakes

1197 Views 11 Replies 4 Participants Last post by  Jcote
So I have a 2015 Cruze Lt 6 spd 1.4. stock brakes all around except drilled and slotted rotors in the front.

About 2 months ago, and gradually getting worse over time, every time I press or release the brake pedal especially when still or at very slow speeds like a drive thru, this robotic arm sound happens. That's the best I could describe it. Now, I know I have a major vac leak I need to fix from the pcv fix kit having the the valve come loose in the manifold, but I think it's the vacuum assist for the brakes. Or rather, the electrical vacuum pump for it. Attached is a video that should show what it's doing.

Any thoughts? Not throwing any codes either. Here is the link to the video below.

Video of issue
1 - 12 of 12 Posts

· Premium Member
Joined
·
3,238 Posts
Check your brake booster line in engine bay for a hole in line which is unlikely or pipe could be clogged with something. Could be even a faulty brake booster part and not the hose keep me posted
 

· Administrator
2014 LT program car, Pull Me Over Red, 1.4T Auto
Joined
·
14,165 Posts
So I have a 2015 Cruze Lt 6 spd 1.4. stock brakes all around except drilled and slotted rotors in the front.

About 2 months ago, and gradually getting worse over time, every time I press or release the brake pedal especially when still or at very slow speeds like a drive thru, this robotic arm sound happens. That's the best I could describe it. Now, I know I have a major vac leak I need to fix from the pcv fix kit having the the valve come loose in the manifold, but I think it's the vacuum assist for the brakes. Or rather, the electrical vacuum pump for it. Attached is a video that should show what it's doing.

Any thoughts? Not throwing any codes either. Here is the link to the video below.

Video of issue
It seemed to increase in volume and tempo when you stepped on the gas, if so, something from the trans or engine may be rubbing.
 

· Registered
Joined
·
85 Posts
I just started noticing this with my Cruze a few days ago…
it set a fault for p0171. I found valve cover bad… Pcv valve is blown out… I’ll be replacing my cover tomorrow or Friday I’ll let you know if the sound goes away.
Considering the brake booster works off vacuum it could be related.
 

· Administrator
2014 LT program car, Pull Me Over Red, 1.4T Auto
Joined
·
14,165 Posts
I just started noticing this with my Cruze a few days ago…
it set a fault for p0171. I found valve cover bad… Pcv valve is blown out… I’ll be replacing my cover tomorrow or Friday I’ll let you know if the sound goes away.
Considering the brake booster works off vacuum it could be related.
The valve cover is just a symptom. The valve you are referring to is the vacuum regulator. The culprit is the PCV valve in the intake. Consider buying a V3.4 kit to fix the main issue before more of the other symptoms start as it is cheaper than replacing the intake manifold.

 

· Registered
Joined
·
85 Posts
The valve cover is just a symptom. The valve you are referring to is the vacuum regulator. The culprit is the PCV valve in the intake. Consider buying a V3.4 kit to fix the main issue before more of the other symptoms start as it is cheaper than replacing the intake manifold.

thos has already been done. But Vac regulator again. Check valves are operating properly. But I am changing them again…

also car has 360k might have slightly higher then normal crank case. Pressure.
I have new car ordered. Just need this to last me a. Few more months
 

· Registered
Joined
·
85 Posts
So I have a 2015 Cruze Lt 6 spd 1.4. stock brakes all around except drilled and slotted rotors in the front.

About 2 months ago, and gradually getting worse over time, every time I press or release the brake pedal especially when still or at very slow speeds like a drive thru, this robotic arm sound happens. That's the best I could describe it. Now, I know I have a major vac leak I need to fix from the pcv fix kit having the the valve come loose in the manifold, but I think it's the vacuum assist for the brakes. Or rather, the electrical vacuum pump for it. Attached is a video that should show what it's doing.

Any thoughts? Not throwing any codes either. Here is the link to the video below.

Video of issue
I had this going on. Replaced my Valve cover today due to vacuum regulator failing and it seems to have fixed the odd “robotic noise” if I was hearing the same thing as you are. Once you fix your Pcv system it may go away as well.
 

· Administrator
2014 LT program car, Pull Me Over Red, 1.4T Auto
Joined
·
14,165 Posts
thos has already been done. But Vac regulator again. Check valves are operating properly. But I am changing them again…

also car has 360k might have slightly higher then normal crank case. Pressure.
I have new car ordered. Just need this to last me a. Few more months
Also test your O2 sensors.

 

· Administrator
2014 LT program car, Pull Me Over Red, 1.4T Auto
Joined
·
14,165 Posts
would I not be able to do this by monitoring the O2 sensor voltage on my OBD reader?
I read one article saying to monitor it and as long as it’s between 0.1v and 0.8 it’s good.
Yes, you should be able to monitor with the OBDII reader. You need to look at both sensors. They will have different patterns unless one is bad.

 

· Registered
Joined
·
85 Posts
Yes, you should be able to monitor with the OBDII reader. You need to look at both sensors. They will have different patterns unless one is bad.
I’m
here is a link to myO2 sensor readings I believe they are good, also they are in closed loop.


Also my Fuel trims before and after cover replacement




from what I read in here that’s pretty good for a cruZe.
 
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top