• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Do I have a vacuum leak?

  • Thread starter Thread starter SR97GT66
  • Start date Start date Dec 6, 2003

SR97GT66

New Member
Jan 19, 2003
281
0
0
Long Island, NY
Dec 6, 2003
#1
  • Dec 6, 2003
  • #1
Now that I've got my '66 running, when I hit the gas the car barely goes. I was flooring it and going like 15 mph. Basically it seemed like it wasn't shifting into second gear. What could be causing this? A vacuum leak maybe? It's a 289 w/ a c4. This was never a problem before I let it sit for 8 months. I added some tranny sealer to see if that would help but no luck. Thanks.
-Scott
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Dec 6, 2003
#2
  • Dec 6, 2003
  • #2
Check the trans fluid level, sounds like it's low.

PB
 

SR97GT66

New Member
Jan 19, 2003
281
0
0
Long Island, NY
Dec 6, 2003
#3
  • Dec 6, 2003
  • #3
I did that already. It was low after we got it started but I filled it up.
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Dec 6, 2003
#4
  • Dec 6, 2003
  • #4
SR97GT66 said:
I did that already. It was low after we got it started but I filled it up.
Click to expand...

Did you run it thru the gear pattern then recheck the fluid level?
they will sometimes need more fluid after it has pumped thru the system.

PB
 

SR97GT66

New Member
Jan 19, 2003
281
0
0
Long Island, NY
Dec 6, 2003
#5
  • Dec 6, 2003
  • #5
No I didn't recheck the level I'll do that once these 20+ inches of snow melts. Thanks.
-Scott
 
You must log in or register to reply here.

Similar threads

Mustang II 4 cyl gear hunting and possibly messed up vacuum system
  • oesterreicher
  • May 31, 2026
  • 1974 - 1978 Mustang II Talk & Tech
Replies
11
Views
211
1974 - 1978 Mustang II Talk & Tech Jun 14, 2026
manicmechanic007
S
I don know what im doing!
  • Sha_lala_pookie
  • May 5, 2025
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
11
Views
500
1965 - 1973 Classic Mustangs -General/Talk- May 11, 2025
Sha_lala_pookie
S
8
Engine Rough idle and aggressive sputtering when accelerating
  • 88vertible
  • Aug 13, 2025
  • Fox 5.0 Mustang Tech
Replies
4
Views
1K
Fox 5.0 Mustang Tech Dec 13, 2025
Jarhead67
J
A
2001 Mustang GT, scorched metal smell and noise from trans/diff?
  • AndyE2255
  • Dec 1, 2025
  • SN95 4.6L Mustang Tech
Replies
4
Views
424
SN95 4.6L Mustang Tech Dec 28, 2025
gkomo
is my car dead
  • kenzo0315
  • Jun 30, 2025
  • SN95 V6 Mustang Tech
  • 2
Replies
29
Views
1K
SN95 V6 Mustang Tech Jul 8, 2025
kenzo0315
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?