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1970 Mustang Coupe-- Hesitation When Accelerating Question

  • Thread starter Thread starter Nick Bos
  • Start date Start date Dec 7, 2016
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    1970 1970 mustang 302 acceleration hesitation problem problems trouble wont apply power

Nick Bos

Member
Dec 7, 2016
20
2
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Dec 7, 2016
#1
  • Dec 7, 2016
  • #1
Hello all,

I am new to forums in general and I thought the perfect time to join one is when I purchased a classic mustang.

Anyways the problem I'm having is whenever I hit the gas hard, the car hesitates for about 2-3 seconds then finally revs up and goes. Its pretty bothersome and annoying at times when I wanna punch it. The engine is a 302-2v with a 2 barrel carb.

I'm not sure if its the carb or maybe timing. It idles well and accelerates well, but there is just a hesitation to apply power.

Any help will be much appreciated, thank you.
 

Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
Mar 7, 2002
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Dec 7, 2016
#2
  • Dec 7, 2016
  • #2
Those old 2100 carburetors are just about the easiest to work on. Get the numbers off of it, get a GP Sorensen rebuild kit for it, and rebuild it. After that, tune and adjust things accordingly.
 

horse sence

15 Year Member
Nov 29, 1999
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Wile Coyote's stunt double
Dec 7, 2016
#3
  • Dec 7, 2016
  • #3
It sounds like possibly the accelerator pump ,i have had Holleys do the same thing .The new gas hardens the accelerator pump and it will be slow delivering a squirt of fuel for quick acceleration ,it may even stop squirting fuel altogether . I believe the auto lite /motor craft carb uses the same pump as the Holley ,get the green pump for alcohol and it should clear it up .
 

tos

Founding Member
Apr 27, 2001
896
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Cincinnati Ohio
Dec 8, 2016
#4
  • Dec 8, 2016
  • #4
I second the accelerator pump. Diaphragm is probly old, brittle, cracked, dried out etc.
it also could just need adjusting. If misadjustmed it will squirt late. Its real simple to just pop it off though and look at it.
 

Nick Bos

Member
Dec 7, 2016
20
2
13
Dec 8, 2016
#5
  • Dec 8, 2016
  • #5
Thanks a lot guys! I haven't done anything at the moment but when the weekend rolls around I'll check out that accelerator pump. The carb definitely needs work since it's the original 2 barrel.
 
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