66 Mustang shuts off

I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and was
running well until this weekend. Now, it cranks easily, idles a little rough,
and operates fine at a high speed. But when I let off the accelerator, the
engine cuts off. If I deaccelerate and put it in neutral and rev the engine,
I can keep it going. But as soon as I give it gas, it shuts off again. Any
idea what is going on? Thanks.

Carolina Girl wrote:

> I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and was
> running well until this weekend. Now, it cranks easily, idles a little rough,
> and operates fine at a high speed. But when I let off the accelerator, the
> engine cuts off. If I deaccelerate and put it in neutral and rev the engine,
> I can keep it going. But as soon as I give it gas, it shuts off again. Any
> idea what is going on? Thanks.

Check your fuel pressure.

--
..boB
Arrived: 2006 FXDI, Red.
1997 HD FXDWG - Turbocharged Stolen 11/26/05 in Denver
1HD1GEL10VY3200010 CO License J5822Z
2001 Dodge Dakota QC 5.9/4x4/3.92
1966 Mustang Coupe - Daily Driver
1965 FFR Cobra - 427W EFI, Damn Fast.

"Carolina Girl" <u23084@uwe> wrote in message news:61d6498bc6173@uwe...
>I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and
>was
> running well until this weekend. Now, it cranks easily, idles a little
> rough,
> and operates fine at a high speed. But when I let off the accelerator,
> the
> engine cuts off. If I deaccelerate and put it in neutral and rev the
> engine,
> I can keep it going. But as soon as I give it gas, it shuts off again.
> Any
> idea what is going on? Thanks.

Sounds like your idle adjust is set too low on the carb.
--
Scott W.
'68 Ranchero 500 302
'69 Mustang Sportsroof 351W
ThunderSnake #57
http://home.comcast.net/~vanguard92/

From: u23084@uwe (Carolina*Girl)

I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and
was running well until this weekend. Now, it cranks easily, idles a
little rough, and operates fine at a high speed. But when I let off the
accelerator, the engine cuts off. If I deaccelerate and put it in
neutral and rev the engine, I can keep it going. But as soon as I give
it gas, it shuts off again. Any idea what is going on? Thanks.

=======
on the old carb units, there are six individual systems that make up
the carb. they all work together, and when one of the systems act up,
we tend to say the word, 'carb' instead of the single system that is
giving the trouble.

as you have pointed out, everything is working except the idle system.
that is where you need to look for the problem.

you say if runs fine when you are using the partial and main metering
systems, the accelerator pump system, and full throttle system.

what happens is when you let off the gas, is that it shifts the
responsibility of the carb back on the idle system, which it is failing,
thus causing the engine to die.

some of the problems in the idle system, can be everything from mixture
screws out of adjustment, fuel bowl level is not correct, (included in
this is dirt sticking the needle valve open), or to much air mixing with
the fuel (leaking gaskets) there are more things that can cause this,
but this is a start. hope it helps.

~ curtis

knowledge is power - growing old is mandatory - growing wise is optional
"Many more men die with prostate cancer than of it. Growing old is
invariably fatal. Prostate cancer is only sometimes so."
http://community.webtv.net/PALMER_ENT/doc

"Carolina Girl" <u23084@uwe> wrote in message news:61d6498bc6173@uwe...
>I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and
>was
> running well until this weekend. Now, it cranks easily, idles a little
> rough,
> and operates fine at a high speed. But when I let off the accelerator,
> the
> engine cuts off. If I deaccelerate and put it in neutral and rev the
> engine,
> I can keep it going. But as soon as I give it gas, it shuts off again.
> Any
> idea what is going on? Thanks.

accelerator pump...small diaphragm on the front of the carb..spits a
measured amount of raw fuel into the systems to overcome the tempaory lean
condition when you step on the gas pedal.

We need more info to help more. Need to know what kind of carb you have for
more specific instructions on what to try. Do you have a 2bbl or 4 bbl? Is
it the original Autolite, or a Holley, Edelbrock/Carter?
--
Scott W.
'68 Ranchero 500 302
'69 Mustang Sportsroof 351W
ThunderSnake #57
http://home.comcast.net/~vanguard92/

thanks for the suggestion.
Blue Mesteno wrote:
>>I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and
>>was
>[quoted text clipped - 7 lines]
>> Any
>> idea what is going on? Thanks.
>
>Sounds like your idle adjust is set too low on the carb.

--
1966 Baby Blue Mustang Convertable
I have owned this car since 1977. I got it when I was 16 and I still love my
rag top.

Message posted via http://www.carkb.com

Wow. thanks for the help. I greatly appreciate it.

c palmer wrote:
>From: u23084@uwe (Carolina*Girl)
>
>I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and
>was running well until this weekend. Now, it cranks easily, idles a
>little rough, and operates fine at a high speed. But when I let off the
>accelerator, the engine cuts off. If I deaccelerate and put it in
>neutral and rev the engine, I can keep it going. But as soon as I give
>it gas, it shuts off again. Any idea what is going on? Thanks.
>
>=======
>on the old carb units, there are six individual systems that make up
>the carb. they all work together, and when one of the systems act up,
>we tend to say the word, 'carb' instead of the single system that is
>giving the trouble.
>
>as you have pointed out, everything is working except the idle system.
>that is where you need to look for the problem.
>
>you say if runs fine when you are using the partial and main metering
>systems, the accelerator pump system, and full throttle system.
>
>what happens is when you let off the gas, is that it shifts the
>responsibility of the carb back on the idle system, which it is failing,
>thus causing the engine to die.
>
>some of the problems in the idle system, can be everything from mixture
>screws out of adjustment, fuel bowl level is not correct, (included in
>this is dirt sticking the needle valve open), or to much air mixing with
>the fuel (leaking gaskets) there are more things that can cause this,
>but this is a start. hope it helps.
>
>~ curtis
>
>knowledge is power - growing old is mandatory - growing wise is optional
>"Many more men die with prostate cancer than of it. Growing old is
>invariably fatal. Prostate cancer is only sometimes so."
>http://community.webtv.net/PALMER_ENT/doc

--
1966 Baby Blue Mustang Convertable
I have owned this car since 1977. I got it when I was 16 and I still love my
rag top.

Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...stang/200606/1

thanks for the information
walt peifer wrote:
>>I have a 1966 Mustang with a V8 289 engine. It was recently tuned up and
>>was
>[quoted text clipped - 7 lines]
>> Any
>> idea what is going on? Thanks.
>
>accelerator pump...small diaphragm on the front of the carb..spits a
>measured amount of raw fuel into the systems to overcome the tempaory lean
>condition when you step on the gas pedal.

--
1966 Baby Blue Mustang Convertable
I have owned this car since 1977. I got it when I was 16 and I still love my
rag top.

Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...stang/200606/1