Do I Need to Plug the Vacuum Line When Removing an Air Force One Controller?

Updated 12/30/2025 | Published 12/25/2025

Question:

Im removing a Air Force 1 tow bumper and controller. Do i just plug the vacuum line that goes into the controller if i remove it?

asked by: Alec S

Expert Reply:

Hello Alec,

Yes, if you’re removing the Air Force One controller from # SM99243, you will want to cap the vacuum line that was feeding it. That line pulls engine vacuum, so it cannot be left open once the controller is gone.

The easiest and cleanest way to do this is with a rubber vacuum cap sized to the hose. If you do not have one handy, you can slide a short bolt or screw into the hose and secure it with a clamp. The important part is making sure the seal is airtight so there is no vacuum leak.

This step matters because an open vacuum line will cause a vacuum leak, which can lead to rough idling, a check engine light, reduced brake assist, or the engine running lean. Capping it properly prevents all of those issues.

For the bumper mounted Air Force One components, the air line from the quick connect can simply be removed. Since it will no longer be connected to a pressurized air source, there is nothing on that side that needs to be capped. The engine vacuum line is the only critical one.

After everything is removed and capped, it is a good idea to start the vehicle and let it idle for a minute. Listen for any hissing sounds and press the brake pedal to make sure it feels normal and not overly hard.

Are you hanging you flat towing keys up for good, or just going to be getting a different vehicle?

expert reply by: Kate F

Alec S.

12/29/2025

Thanks! That's a perfect description. We bought the vehicle used with this equipment already installed. It's for my son, so he will not be flat towing in the foreseeable future. Your support reply has been awesome, though. Thank you for the complete response.