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  • 1965 - 1973 Classic Mustangs -General/Talk-

c4 tranny

  • Thread starter Thread starter will34
  • Start date Start date May 4, 2020
W

will34

Member
Jun 16, 2019
18
1
13
ontario
May 4, 2020
#1
  • May 4, 2020
  • #1
I have 1969 c4 tranny. It will not shift from first to second when put into drive. I have been as high 3000 rpm. It will shift from second to third when starting off in D2.
 
G

gmgouin

15 Year Member
Jul 9, 2012
8
3
13
May 4, 2020
#2
  • May 4, 2020
  • #2
Probably a vacuum line signal loss.
 

horse sence

15 Year Member
Nov 29, 1999
12,179
8,001
233
Wile Coyote's stunt double
May 4, 2020
#3
  • May 4, 2020
  • #3
Vacuum line or maybe blown out modulator valve
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
May 4, 2020
#4
  • May 4, 2020
  • #4
yep, sounds like vacuum modulator issues. either no vacuum, bad modulator, or bad adjustment on the modulator(yes some are adjustable).
 
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