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Possible Vacuum Leak 67 Mustang

  • Thread starter Thread starter jackson0215
  • Start date Start date May 1, 2019

jackson0215

Member
Dec 10, 2009
101
3
19
May 1, 2019
#1
  • May 1, 2019
  • #1
I finally started my 67 and I have an issue that I think is a vacuum leak but I wanted to see if anyone else had any ideas. It is a rebuilt 390, new comp cap, new Pertronix distributer, new Quick Fuel Carb and Edelbrock intake.

When it starts it takes a little feathering to keep it going and if you give it gas it boggs down and sputters. . After a few minutes the idle increases to 2000 RPM but the accelerator has not moved and the butter flys is not open. Nothing really makes it slow back down but eventually does. It never really smooths out and becomes responsive.

I do not have power brakes and it is a 4 speed car. I have checked the vacuum ports on the carb and changed the gasket between the intake and spacer and the spacer to the carb. I am thinking it is a vacuum leak on the intake.

Any thoughts would be appreciated.
Thank you,
Jackson
 
R

rgsauger

Member
Aug 8, 2018
48
10
18
Houston
May 30, 2019
#2
  • May 30, 2019
  • #2
Spray the sides and base of the carb and intake with carb cleaner and you can tell if it's a vacuum leak.

Also check your choke settings.
 

2Blue2

will be trying this sex one when I can find it
Mod Dude
Mar 5, 2019
4,430
2,893
163
Oahu
May 30, 2019
#3
  • May 30, 2019
  • #3
Were the heads milled and the block decked? FE intake gaskets some times slide down a little and or don't seal well 'after machine work' on the bottom of the port, inside the lifter valley.
Good luck, hope you figure it out.
 
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