2.5L backfires
08-14-2005, 01:54 AM
#11
Guest
Posts: n/a
Re: 2.5L backfires
Fix the leak in your exhaust headers.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Carl Saiyed wrote:
>
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about 5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Carl Saiyed wrote:
>
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about 5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
08-14-2005, 01:54 AM
#12
Guest
Posts: n/a
Re: 2.5L backfires
Fix the leak in your exhaust headers.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Carl Saiyed wrote:
>
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about 5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Carl Saiyed wrote:
>
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about 5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
08-14-2005, 01:54 AM
#13
Guest
Posts: n/a
Re: 2.5L backfires
Fix the leak in your exhaust headers.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Carl Saiyed wrote:
>
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about 5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Carl Saiyed wrote:
>
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about 5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
08-14-2005, 09:58 AM
#14
Guest
Posts: n/a
Re: 2.5L backfires
Bill,
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
08-14-2005, 09:58 AM
#15
Guest
Posts: n/a
Re: 2.5L backfires
Bill,
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
08-14-2005, 09:58 AM
#16
Guest
Posts: n/a
Re: 2.5L backfires
Bill,
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
08-14-2005, 09:58 AM
#17
Guest
Posts: n/a
Re: 2.5L backfires
Bill,
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
The two classic causes of backfire on deceleration are exhaust leak, and
idle mixture too lean. Hot idle dropping to 5-600 rpm, makes me think the
idle mixture could be too lean.
Carl, if you cannot find an exhaust leak, clean the throttle body, check the
operation of the Idle Speed Adjustment motor, replace the fuel filter
(probably needs it anyway), and check for vacuum leaks.
Earle
"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:42FEDC85.D0F82F89@***.net...
> Fix the leak in your exhaust headers.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Carl Saiyed wrote:
> >
> > The 2.5L in my 89 YJ has been backfiring for a while. When cold, it
idles
> > smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> > but sometimes is smooth. Sometimes it will backfire on deceleration.
This is
> > only usually if you downshift to slow down. The backfiring is pretty
bad,
> > sounds like a gunshot. There is a hesitation off idle. Typically, the
rpms
> > will drop before rising when I press the gas pedal. This is all pretty
much
> > when the engine is warm. It's not over heating. I used to smell gas
fumes
> > when it was cold. Lastly, the tail pipe is pretty black on the inside.
> >
> > Where do I even start?
> >
> > Carl
08-14-2005, 02:07 PM
#18
Guest
Posts: n/a
Re: 2.5L backfires
an intake manifold leak can cause a lean problem. To check, spray starter
fluid around the intake manifold gasket. An increase in engine speed
signifies a leak. A dealer did this to my '89, and found the intake
manifold gasket was leaking. He simply adjusted the carb idle jets to
compensate....an easy and cheap fix... But maybe this is not your
problem..??
"Carl Saiyed" <carlsaiyed@REMOVEhotmail.com> wrote in message
news:42fecfb6$1_5@newsfeed.slurp.net...
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This
is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty
much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
>
>
fluid around the intake manifold gasket. An increase in engine speed
signifies a leak. A dealer did this to my '89, and found the intake
manifold gasket was leaking. He simply adjusted the carb idle jets to
compensate....an easy and cheap fix... But maybe this is not your
problem..??
"Carl Saiyed" <carlsaiyed@REMOVEhotmail.com> wrote in message
news:42fecfb6$1_5@newsfeed.slurp.net...
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This
is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty
much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
>
>
08-14-2005, 02:07 PM
#19
Guest
Posts: n/a
Re: 2.5L backfires
an intake manifold leak can cause a lean problem. To check, spray starter
fluid around the intake manifold gasket. An increase in engine speed
signifies a leak. A dealer did this to my '89, and found the intake
manifold gasket was leaking. He simply adjusted the carb idle jets to
compensate....an easy and cheap fix... But maybe this is not your
problem..??
"Carl Saiyed" <carlsaiyed@REMOVEhotmail.com> wrote in message
news:42fecfb6$1_5@newsfeed.slurp.net...
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This
is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty
much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
>
>
fluid around the intake manifold gasket. An increase in engine speed
signifies a leak. A dealer did this to my '89, and found the intake
manifold gasket was leaking. He simply adjusted the carb idle jets to
compensate....an easy and cheap fix... But maybe this is not your
problem..??
"Carl Saiyed" <carlsaiyed@REMOVEhotmail.com> wrote in message
news:42fecfb6$1_5@newsfeed.slurp.net...
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This
is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty
much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
>
>
08-14-2005, 02:07 PM
#20
Guest
Posts: n/a
Re: 2.5L backfires
an intake manifold leak can cause a lean problem. To check, spray starter
fluid around the intake manifold gasket. An increase in engine speed
signifies a leak. A dealer did this to my '89, and found the intake
manifold gasket was leaking. He simply adjusted the carb idle jets to
compensate....an easy and cheap fix... But maybe this is not your
problem..??
"Carl Saiyed" <carlsaiyed@REMOVEhotmail.com> wrote in message
news:42fecfb6$1_5@newsfeed.slurp.net...
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This
is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty
much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
>
>
fluid around the intake manifold gasket. An increase in engine speed
signifies a leak. A dealer did this to my '89, and found the intake
manifold gasket was leaking. He simply adjusted the carb idle jets to
compensate....an easy and cheap fix... But maybe this is not your
problem..??
"Carl Saiyed" <carlsaiyed@REMOVEhotmail.com> wrote in message
news:42fecfb6$1_5@newsfeed.slurp.net...
> The 2.5L in my 89 YJ has been backfiring for a while. When cold, it idles
> smooth and runs fine. When hot the idle can drop as low as about
5-600rpms,
> but sometimes is smooth. Sometimes it will backfire on deceleration. This
is
> only usually if you downshift to slow down. The backfiring is pretty bad,
> sounds like a gunshot. There is a hesitation off idle. Typically, the rpms
> will drop before rising when I press the gas pedal. This is all pretty
much
> when the engine is warm. It's not over heating. I used to smell gas fumes
> when it was cold. Lastly, the tail pipe is pretty black on the inside.
>
> Where do I even start?
>
> Carl
>
>