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  • 1965 - 1973 Classic Mustangs -General/Talk-
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what could be wrong

  • Thread starter Thread starter SLEEPERstang21
  • Start date Start date Nov 16, 2004
S

SLEEPERstang21

Founding Member
Feb 15, 2002
204
0
0
Sunny California
Nov 16, 2004
#1
  • Nov 16, 2004
  • #1
whenever i turn my car off it diesels for a little bit and then sputters gas out of the carb. what can be wrong?
 

reenmachine

20+ Year Stangneter
Jun 27, 2004
1,258
2
38
Montrose, CA
Nov 16, 2004
#2
  • Nov 16, 2004
  • #2
SLEEPERstang21 said:
whenever i turn my car off it diesels for a little bit and then sputters gas out of the carb. what can be wrong?
Click to expand...
Lemme guess since there's not much info here...lotsa miles with no rebuild?

Big time carbon buildup on your valves and/or plugs could make it diesel.
 
S

SLEEPERstang21

Founding Member
Feb 15, 2002
204
0
0
Sunny California
Nov 16, 2004
#3
  • Nov 16, 2004
  • #3
the 289 was rebuilt few years back. just a few months ago i got the heads redone, and new plugs
 
O

Ozsum2

New Member
Jul 28, 2004
695
1
0
Nov 16, 2004
#4
  • Nov 16, 2004
  • #4
What is your timing set at and your idle rpm? Could be that both are advanced too much.
 

65fastback2+2

New Member
Aug 4, 2003
1,229
0
0
Louisville, KY
Nov 16, 2004
#5
  • Nov 16, 2004
  • #5
Ozsum2 said:
What is your timing set at and your idle rpm? Could be that both are advanced too much.
Click to expand...

that was gonna be my reply!
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Nov 16, 2004
#6
  • Nov 16, 2004
  • #6
I go with the High idle.
 

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Nov 16, 2004
#7
  • Nov 16, 2004
  • #7
Ozsum2 said:
What is your timing set at and your idle rpm? Could be that both are advanced too much.
Click to expand...

Correctamundo!

Until you fix it, shut it off in gear if it is an automatic, or slightly engage the clutch if it is a manual. The extra resistance will prevent it from happening. Letting the engine run on is pretty bad for it.
 

Shocwave04

New Member
Nov 17, 2004
78
0
0
Austin (from Dallas)
Nov 17, 2004
#8
  • Nov 17, 2004
  • #8
Re

Man.... I had this same problem... its the vacum advance. And yes hes right. Until you fix it shut it off in gear.
 
O

Ozsum2

New Member
Jul 28, 2004
695
1
0
Nov 17, 2004
#9
  • Nov 17, 2004
  • #9
Shocwave04 said:
Man.... I had this same problem... its the vacum advance. And yes hes right. Until you fix it shut it off in gear.
Click to expand...



Vacum advance??? Huhhhhh? Do you mean the timing is just too far forward like I said, or do you really mean vac advance?
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Nov 17, 2004
#10
  • Nov 17, 2004
  • #10
Ozsum2 said:
Vacum advance??? Huhhhhh? Do you mean the timing is just too far forward like I said, or do you really mean vac advance?
Click to expand...

To much Pot does that
 
R

Rumble

New Member
Nov 15, 2004
21
0
0
Ontario, Canada
Nov 17, 2004
#11
  • Nov 17, 2004
  • #11
If it just started it could be fuel related. Are you buying lower-octane gas than before? Or maybe they started blending in octane? Or maybe the local stations have switched to winter fuel which is more volatile and prone to dieseling?

Any of these could be a factor, if the dieseling just started out of the blue. Whatever the cause, take it seriously.
 

thehueypilot

Active Member
Feb 25, 2004
1,084
0
37
Medina,Tennessee
Nov 17, 2004
#12
  • Nov 17, 2004
  • #12
WORTH said:
To much Pot does that
Click to expand...

Now that was funny......I laughed out loud at that one! Thanks Worth!
 

Shocwave04

New Member
Nov 17, 2004
78
0
0
Austin (from Dallas)
Nov 17, 2004
#13
  • Nov 17, 2004
  • #13
re

Well when this happened to me it was the VA when i replaced it the problem was gone
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Nov 17, 2004
#14
  • Nov 17, 2004
  • #14
Only one thing causes it, the throttle blades are open too far, allowing enough fuel/air mixture in to feed the dieseling. Close the throttle blades and the problem will disappear. Use the timing and or mixture screws to raise the idle speed to where the engine will idle where you want it.
 
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