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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

starts and runs but doesnt stay running - carbed

  • Thread starter Thread starter nicefighter80
  • Start date Start date Mar 6, 2010
N

nicefighter80

New Member
Dec 10, 2009
13
0
0
Mar 6, 2010
#1
  • Mar 6, 2010
  • #1
85 306 roller with edlebrock rpm intake(dual plane), holley 600 cfm carb with vacuum secondaires, MSD 6AL box and a msd cap, vacuum advance dist., gt40 heads, carter external fuel pump, 3/8(i think) braided steel fuel lines, stock serptine belt set up, i think thats all i can remember but feel free to ask
imhaving problems getting it to start but once it starts its not wanting to stay running, the carb, wires and plugs are brand new.

im thinking its the timing because when i threw the light on it, it was reading around 25 at 1500 rpms is that even right?
 
N

nicefighter80

New Member
Dec 10, 2009
13
0
0
Mar 6, 2010
#2
  • Mar 6, 2010
  • #2
i got it to run, but it has a off idle hesitation and im know sure why any ideas?
 
D

DonMaximo

Member
Sep 25, 2003
217
5
19
Lewisville, Texas
Mar 6, 2010
#3
  • Mar 6, 2010
  • #3
Off-idle hesitation ?

Check your squirter on the carb...with the lack of info... can't really determine if you're coming in rich or lean and causing the hesitation.
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
5,222
3,254
204
South Jersey
Mar 7, 2010
#4
  • Mar 7, 2010
  • #4
Deffinatly sounds like a carb issue. What's your fuel pressure?
 
N

nicefighter80

New Member
Dec 10, 2009
13
0
0
Mar 9, 2010
#5
  • Mar 9, 2010
  • #5
FP is at 6 psi carb is a brand new holley 600 cfm vac sec. i think im leaning out but i didnt think i would lean out off idle could the timing be to retarded?
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
5,222
3,254
204
South Jersey
Mar 9, 2010
#6
  • Mar 9, 2010
  • #6
Has it done this since you installed the carb? I have seen a lot of problems w/ the new holley carbs. The menthanol they put in the fuel these days really eats at the coating on the metering blocks. If you pull the carb apart to clean it, you will find a ton of flaky material in side it. I would start there, and if that doesn't help maybe try a bigger squirter.
 
N

nicefighter80

New Member
Dec 10, 2009
13
0
0
Mar 9, 2010
#7
  • Mar 9, 2010
  • #7
well the carb is new like its never been on the road new it will idle fine but when you drive it, its got a bad hestitation till 2500 rpm im not sure why
 

Celeb

20+ Year Stangneter
Sep 8, 2002
736
13
59
Here and there
Mar 9, 2010
#8
  • Mar 9, 2010
  • #8
Turn the idle mixture screws all the way in and then back them out a turn and a half. Hook up a vacuum gauge and shoot for the highest vacuum at idle while adjusting the screws. Turn them both equal amounts, maybe a quarter turn at a time while checking vacuum.
 
N

nicefighter80

New Member
Dec 10, 2009
13
0
0
Mar 10, 2010
#9
  • Mar 10, 2010
  • #9
what will turning the idle screws do? not saying your wrong i just like to understand the concepts so i can help people trouble shoot on down the road
 
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