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Discussion Starter · #1 ·
So this started happening out of nowhere. When I brake and come to a stop. The whole car shakes violently. There is no general area where the shaking is coming from, it’s just the whole car. My ABS light is on and the code I got was 005241 Brake boost vacuum system, mechanical failure. I was going to replace the pump but I decided to just take it apart and clean it. That only improved it by about ten to fifteen percent. I decided to make my own post because the other forums and threads that I’ve read don’t have similar symptoms, just the fault codes. I don’t know if it’s my check valves or pump or the actual booster. I want to fix it because having to put the car in neutral every time I come to a stop is not the most ideal situation, and traction control would be nice. Could use some help to figure it out.
 

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A full scan with VCDS or similar would be a big help.
The only thing that can cause the shaking as you have described is a misfiring engine.
I suggest you check the link posted by AndreasPassat
Check all vac lines & check valves for leaks, and check all of the PCV system.

It appears likely that you also have a faulty ABS module, I suggest you send it out for repair.
 

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Discussion Starter · #7 ·
A full scan with VCDS or similar would be a big help.
The only thing that can cause the shaking as you have described is a misfiring engine.
I suggest you check the link posted by AndreasPassat
Check all vac lines & check valves for leaks, and check all of the PCV system.

It appears likely that you also have a faulty ABS module, I suggest you send it out for repair.
I know it’s not a misfire. It only happens when I’m in drive. I’ll post a video. Pcv system was replaced a year ago due to the misfire. There are a couple check valves that I could replace but I’m fairly certain it’s not the problem. I’ll post a video if I can. I also replaced the abs module about a year ago
 

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Discussion Starter · #8 ·
I know it’s not a misfire. It only happens when I’m in drive. I’ll post a video. Pcv system was replaced a year ago due to the misfire. There are a couple check valves that I could replace but I’m fairly certain it’s not the problem. I’ll post a video if I can. I also replaced the abs module about a year ago
Couldn’t post a video. Here’s a link to where I uploaded it on YouTube. Hope this helps y’all understand it better. It’s hard to describe the shaking to where people don’t think it’s something else
 

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Update. I cannot find the fuse. Also. Car shakes more when under electrical load. I turned on my brights and the shaking got worse. Then even more so when I turned on night lights and my light bar
Look here: Where is the brake booster fuse?

I would take a look at the alternator, too. Any strange noises? When running, measure the voltage at the battery with a multimeter and then switch those items on and see what the readings are.
 

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I would try and get a scan done with VCDS. There's a check engine light on so I would wager to guess that is either contributing to or is an additional underlying problem.
 

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Discussion Starter · #13 ·
I would try and get a scan done with VCDS. There's a check engine light on so I would wager to guess that is either contributing to or is an additional underlying problem.
Check engine light is for an 02 sensor wire. When I erase the codes the check engine goes away until the second turn over but the abs never goes away.
102585
102586
 

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Go over the entire brake vacuum circuit. If there is a leak anywhere, it can cause the pump to run excessively, setting the code. Suction jet pump is a common break.
 

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Discussion Starter · #15 ·
Go over the entire brake vacuum circuit. If there is a leak anywhere, it can cause the pump to run excessively, setting the code. Suction jet pump is a common break.
Just pulled hoses. No visible rips, tears, or holes. Sealed off ends and ran air through. No leaks
 

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Disconnect the large connector from the ABS module, and let us know if that makes a difference.
 

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Discussion Starter · #18 ·
Disconnect the large connector from the ABS module, and let us know if that makes a difference.
Disconnected the module. Brake light came on. Pedal got more stiff. Shaking persisted. Don’t know if I just not started hearing it or if it got worse but there is a new noise.
 

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That last video, what is that?
Mount the camera on a stand sitting on the ground pointed at the engine or the car body will a be a better testament as to what is actually 'shaking'. Is the car sitting on all 4 tires on the ground?

I can hear a faint tell tale sign of clicking, I'm calling it, the ABS pump is faulty.
I'll eat my words in the end if I'm wrong.

Have you put a vacuum gauge on the engine while it's running?
 

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Ok, another thought. Did this violent shaking and the brake code occur at the same time? Many times, when someone posts something up and there are a couple of issues, it makes it sound to other members that they are related, so we try to find a common fault. Maybe those two things are NOT related in this case.

Have you by chance replaced the front axles with aftermarket axles recently? At a stop in drive, many solid aftermarket axles will cause the entire car to shake. That symptom has been well documented.
 
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