Trying to find vacuum port?

2003 MERCURY SABLE
140,000 MILES • V6 • AUTOMATIC
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BRANDON0999
  • MEMBER
  • 1 POST
Trying to find a vacuum leak so I'm trying to see where is the best place to plug my smoke detector on or at.
Sep 29, 2025 at 4:42 AM
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STEVE W.
  • ✓Experienced Mechanic
  • 15,239 POSTS
Have you tried using starting spray on a cold engine first? I find that to be faster than smoke. However if you want to use smoke the easiest way is to put the smoke into the intake at the throttle body and plug the area around it. That fills the intake with smoke and all the lines and ports as well. Then you start sniffing and looking for smoke.
Sep 29, 2025 at 7:52 AM
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STRAILER
  • ✓Experienced Mechanic
  • 55,065 POSTS
Here is the one we use in the shop ($64.00) and a video to show you how.

https://amzn.to/46Jb1gv

Video

https://www.youtube.com/watch?v=LRKWV4Are5c&t

Please let us know what happens.
Sep 30, 2025 at 2:04 AM
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