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2005 Mustang Gt Hesitation Solved !

  • Thread starter Thread starter foxsetup
  • Start date Start date Sep 3, 2017
F

foxsetup

Member
Sep 3, 2017
1
4
13
Sep 3, 2017
#1
  • Sep 3, 2017
  • #1
Hi everyone,

First of all sorry for the bad grammar , I speak french i am from Montréal , Canada.

I've been chasing a bad hesitation with my 2005 mustang gt since LAST SUMMER.I just found out what was the cause of it. If i can help someone with this so you don't have to loose your mind like me i will be more that pleased.
Nothing more simple than a good old vacuum leak...
I knew i had a vacuum leak somewhere but i could not find it because it was no where near the intake.
If you have a procharger with the Proflow bypass valve ( the black one ) PLEASE make a smoke test on it.
The diaphragm Inside of it can go bad and create a really bad leak.

The symptoms were :
LTFT were going high at idle
Intake back fire at low load , low rpm.
weird shifts points.

If you have any of these symptoms and don't know what it is. Make sure to check for vacuum leaks.
 
Reactions: Robert Arco, racerraj, Svtpilot and 1 other person
R

racerraj

Founding Member
Dec 17, 2001
493
32
39
Dickson, TN
Sep 5, 2017
#2
  • Sep 5, 2017
  • #2
Awesome find! Thanks for sharing it for others. And, your grammar is fine.
 
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