Low vacuum
Thread Starter
Newbie
Joined: Apr 2019
Posts: 3
Likes: 2
From: Rocky Mountains
2000 ML320, 2004 C240, 95 BMW 525i
Low vacuum
Hi All,
My ‘04 c240 with 135k miles has an issue with low vacuum that affects the brakes when the car is cold. I live at 7000’. A trusted mechanic diagnosed that the problem was low vacuum (13” when cold IIRC). No leaks were found. He cited a TSB where this issue is sometimes experienced at altitude. The fix calls for the installation of an aux electric vacuum pump. He couldn’t find any info or part numbers.
Does anybody have any experience with this? I know that older muscle cars with modified cams will not produce enough engine vacuum. I’ve read that people bypass engine vacuum all-together and use an electric vacuum pump for the brake booster.
I would rather have the pump assist the brake booster vacuum rather than bypass it all together. To that end there seems to be a Volvo pump and switch that would be easy enough to wire. It would regulate engine vacuum and only come on as needed. I could maybe even add a vacuum canister to store vacuum so the pump doesn’t have to run as much. These are the parts I was thinking about; the switch has a three way valve that attaches to the brake booster with one end going to the pump and the other to the engine.
www.tascaparts.com
And something like this:
www.fcpeuro.com
TIA for any info or guidance!
My ‘04 c240 with 135k miles has an issue with low vacuum that affects the brakes when the car is cold. I live at 7000’. A trusted mechanic diagnosed that the problem was low vacuum (13” when cold IIRC). No leaks were found. He cited a TSB where this issue is sometimes experienced at altitude. The fix calls for the installation of an aux electric vacuum pump. He couldn’t find any info or part numbers.
Does anybody have any experience with this? I know that older muscle cars with modified cams will not produce enough engine vacuum. I’ve read that people bypass engine vacuum all-together and use an electric vacuum pump for the brake booster.
I would rather have the pump assist the brake booster vacuum rather than bypass it all together. To that end there seems to be a Volvo pump and switch that would be easy enough to wire. It would regulate engine vacuum and only come on as needed. I could maybe even add a vacuum canister to store vacuum so the pump doesn’t have to run as much. These are the parts I was thinking about; the switch has a three way valve that attaches to the brake booster with one end going to the pump and the other to the engine.
Vacuum Pump 30641411 | TascaParts.com
30641411 - Vacuum Pump www.tascaparts.comAnd something like this:
Volvo Brake Booster Vacuum Switch - Genuine Volvo 31400693
Volvo Brake Booster Vacuum Switch - Genuine Volvo 31400693www.fcpeuro.com
TIA for any info or guidance!
Newbie
Joined: Jan 2022
Posts: 1
Likes: 0
2006 S500
TSB response
Hi All,
My ‘04 c240 with 135k miles has an issue with low vacuum that affects the brakes when the car is cold. I live at 7000’. A trusted mechanic diagnosed that the problem was low vacuum (13” when cold IIRC). No leaks were found. He cited a TSB where this issue is sometimes experienced at altitude. The fix calls for the installation of an aux electric vacuum pump. He couldn’t find any info or part numbers.
Does anybody have any experience with this? I know that older muscle cars with modified cams will not produce enough engine vacuum. I’ve read that people bypass engine vacuum all-together and use an electric vacuum pump for the brake booster.
I would rather have the pump assist the brake booster vacuum rather than bypass it all together. To that end there seems to be a Volvo pump and switch that would be easy enough to wire. It would regulate engine vacuum and only come on as needed. I could maybe even add a vacuum canister to store vacuum so the pump doesn’t have to run as much. These are the parts I was thinking about; the switch has a three way valve that attaches to the brake booster with one end going to the pump and the other to the engine.
TIA for any info or guidance!
My ‘04 c240 with 135k miles has an issue with low vacuum that affects the brakes when the car is cold. I live at 7000’. A trusted mechanic diagnosed that the problem was low vacuum (13” when cold IIRC). No leaks were found. He cited a TSB where this issue is sometimes experienced at altitude. The fix calls for the installation of an aux electric vacuum pump. He couldn’t find any info or part numbers.
Does anybody have any experience with this? I know that older muscle cars with modified cams will not produce enough engine vacuum. I’ve read that people bypass engine vacuum all-together and use an electric vacuum pump for the brake booster.
I would rather have the pump assist the brake booster vacuum rather than bypass it all together. To that end there seems to be a Volvo pump and switch that would be easy enough to wire. It would regulate engine vacuum and only come on as needed. I could maybe even add a vacuum canister to store vacuum so the pump doesn’t have to run as much. These are the parts I was thinking about; the switch has a three way valve that attaches to the brake booster with one end going to the pump and the other to the engine.
Vacuum Pump 30641411 | TascaParts.com
TIA for any info or guidance!
Best of luck!
