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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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carb. problems

  • Thread starter Thread starter 1985 5.0
  • Start date Start date Apr 14, 2005

1985 5.0

New Member
Apr 10, 2005
42
0
0
Polkville, North Carolina
Apr 14, 2005
#1
  • Apr 14, 2005
  • #1
i got an 85 5.0 with a 4v carbueretor. me and dad went to rebuild it (dad has done this 5 times since having the car) and now it wont idle right. there is an air leak somewhere and all of the vacuum lines appear to be find. we have checked all of the plates and they are all in good condition. It runs perfect at top end with the back 2 barrels coming in strong but when i go up to a stop sign it just goes dead every time because the rpms go straight from 2500 to 0. we have taken it to a local who knows his stuff with carbs. he cant seem to find anything wrong right now the car is at a shop near my house and the guy seems to think that their could be missing a washer somewhere any tips???
 

Stang8URMPRT

Active Member
Dec 28, 2003
1,100
1
38
Daytona Beach, FL
Apr 14, 2005
#2
  • Apr 14, 2005
  • #2
I had the same 4V Holley on my 83 when I got it 575 cfm... If it's still the stock one, I had the same problems when I had mine.... It turned out to be the idle air screws on the sides of the carbs... they were too far in, and it would run awesome but it would die instantly when I tried to let it idle. Hope this helps.
 

green

New Member
Apr 26, 2003
291
0
0
Apr 15, 2005
#3
  • Apr 15, 2005
  • #3
hahahaha the exact same thing with my 85 gt. runs perfet in warm weather but when it starts to get cold out side, as soon as i let off the gas bang she shuts off. with mine running like that i probally get like 12 miles to the gallon, and pretty well near die of gas fumes. but if i run the car for about 10 minuts and shut it off, then let it set 4 about five minuts or so, then start it back up, bang she works like a charm. i never did figure out what the problem is. i,ll need to replace it soon.
 

maverick0716

Founding Member
Jan 12, 2002
3,924
0
56
Chilliwack, BC, Canada
Apr 15, 2005
#4
  • Apr 15, 2005
  • #4
green said:
hahahaha the exact same thing with my 85 gt. runs perfet in warm weather but when it starts to get cold out side, as soon as i let off the gas bang she shuts off. with mine running like that i probally get like 12 miles to the gallon, and pretty well near die of gas fumes. but if i run the car for about 10 minuts and shut it off, then let it set 4 about five minuts or so, then start it back up, bang she works like a charm. i never did figure out what the problem is. i,ll need to replace it soon.
Click to expand...

Haha, I think pretty much all carburators are like that. Even my fairly new Holley 4160 is like that. When it's cold (or humid) out I can warm it up for 5 minutes, but as soon as I let off the gas it dies......but like you I can let it sit for another 3-4 minutes and start it up again, then it runs perfect.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Apr 15, 2005
#5
  • Apr 15, 2005
  • #5
The best solution I can think of is EFI!

This will probably really torque you guys but why fight with old technology?
 
T

ty-rone

New Member
Mar 30, 2005
77
0
0
Apr 15, 2005
#6
  • Apr 15, 2005
  • #6
vristang said:
The best solution I can think of is EFI!

This will probably really torque you guys but why fight with old technology?
Click to expand...


I like your Moxi
 

green

New Member
Apr 26, 2003
291
0
0
Apr 15, 2005
#7
  • Apr 15, 2005
  • #7
it must do it cause its ah holley carb? i mean i know lots of older cars in the 80,s that have a carb engine like the caprices, and chev half ton,s but they never do that. you can start them up in -30 degree weather and they work perfet and never had a problem.
 
M

mackey

Active Member
Jan 25, 2003
1,284
1
38
Beverly, Massachusetts
Apr 15, 2005
#8
  • Apr 15, 2005
  • #8
vristang said:
The best solution I can think of is EFI!

This will probably really torque you guys but why fight with old technology?
Click to expand...

Carb is so much cheaper and why switch when you already have it. You don't need a computer for timing advance and other things.
 

Dark Knight

Founding Member
Feb 1, 2000
2,578
0
0
Chandler, Az.
Apr 15, 2005
#9
  • Apr 15, 2005
  • #9
stock carb? might try all four idle mixture screws, there are 2 on the back too.. all are under the carb, you need an allen wrench to adjust them..

another thing might be the dashpot not working right.. it should kick the idle up when the AC is on, it might be kicking on and off... rasing the idle, then dropping it to far..
 

Fishhawk

New Member
Jun 10, 2004
281
0
0
Michigan City, Indiana
Apr 15, 2005
#10
  • Apr 15, 2005
  • #10
If you decide to go with a new carb, check out QuickFuel Technologies out of Bowling Green Ky. They are former Holley engineers that have redesigned the Holley carb and have made huge improvments. I have a QuickFuel 650 ProVac and have not had any starting or idle problems, rain or shine, hot or cold. Also you can't beat their price. Cheaper then Holley.
 

1985 5.0

New Member
Apr 10, 2005
42
0
0
Polkville, North Carolina
Apr 15, 2005
#11
  • Apr 15, 2005
  • #11
got a call this morning from the auto shop...hes got an 85 5.0 4v too and hes going to try to run his carburetor on it and see if it works- if it works im going to have to get a new carbueretor
 

feifong

New Member
Apr 4, 2005
319
0
0
mesa
Apr 15, 2005
#12
  • Apr 15, 2005
  • #12
could be a messed up plug wire that happend to me
 

Dean85GT

New Member
Nov 27, 2004
502
1
0
Thorold, Ontario, Canada
Apr 15, 2005
#13
  • Apr 15, 2005
  • #13
The same damn thing happens to me. It took 4 starts this morning before my car would start and stay running with my foot on the gas. As soon as it warms up it runs great but until then its awful
 

feifong

New Member
Apr 4, 2005
319
0
0
mesa
Apr 15, 2005
#14
  • Apr 15, 2005
  • #14
Switch to new technology efi??
why fight with old technology?

if its old technology why dont you buy an electric car???
 
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