what could be wrong

[SLEEPERstang21]

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]

whenever i turn my car off it diesels for a little bit and then sputters gas out of the carb. what can be wrong?

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.

 

[SLEEPERstang21]

the 289 was rebuilt few years back. just a few months ago i got the heads redone, and new plugs

 

[Ozsum2]

What is your timing set at and your idle rpm? Could be that both are advanced too much.

 

[65fastback2+2]

What is your timing set at and your idle rpm? Could be that both are advanced too much.

that was gonna be my reply!

 

[WORTH]

I go with the High idle.

 

[Max Power]

What is your timing set at and your idle rpm? Could be that both are advanced too much.

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]

Re

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

 

[Ozsum2]

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

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

 

[WORTH]

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

To much Pot does that

 

[Rumble]

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]

To much Pot does that

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

 

[Shocwave04]

re

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

 

[D.Hearne]

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.