1991 Wrangler 2.5L problem
 

I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
been working on restoring it for a little while but now that I have it
where I can drive it, I have a problem somewhere. I have no clue what
or where the problem is. All I know is that when the engine is at an
idle, it runs very smooth and sounds like a normal engine does. But
when I try to drive it, it starts to backfire really bad, but as soon
as I let off the gas it goes right back to that smooth idle. I have
just about replaced everything in the engine compartment. This problem
has really hendered my progress on getting my jeep road ready. If
anyone can help please let me know. Also does anyone know what the fuel
pressure is supposed to be on this engine?

Thanks
Derrick

Re: 1991 Wrangler 2.5L problem
 

For the 92 Wrangler (YJ) the factory manual says "System fuel pressure
should be approximately 214 kPa (31 psi) with the vacuum line connected
to the regulator. With the vacuum line disconnected from the regulator,
fuel pressure should be approximately 269 kPa (39 psi)"

Stephen.

dwd3773@bellsouth.net wrote:
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick
>

Re: 1991 Wrangler 2.5L problem
 

For the 92 Wrangler (YJ) the factory manual says "System fuel pressure
should be approximately 214 kPa (31 psi) with the vacuum line connected
to the regulator. With the vacuum line disconnected from the regulator,
fuel pressure should be approximately 269 kPa (39 psi)"

Stephen.

dwd3773@bellsouth.net wrote:
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick
>

Re: 1991 Wrangler 2.5L problem
 

For the 92 Wrangler (YJ) the factory manual says "System fuel pressure
should be approximately 214 kPa (31 psi) with the vacuum line connected
to the regulator. With the vacuum line disconnected from the regulator,
fuel pressure should be approximately 269 kPa (39 psi)"

Stephen.

dwd3773@bellsouth.net wrote:
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick
>

Re: 1991 Wrangler 2.5L problem
 

For the 92 Wrangler (YJ) the factory manual says "System fuel pressure
should be approximately 214 kPa (31 psi) with the vacuum line connected
to the regulator. With the vacuum line disconnected from the regulator,
fuel pressure should be approximately 269 kPa (39 psi)"

Stephen.

dwd3773@bellsouth.net wrote:
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick
>

Re: 1991 Wrangler 2.5L problem
 

Could you have 2 plug wires mixed or the wrong rotation on the
distributor cap?

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

dwd3773@bellsouth.net wrote:
>
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick

Re: 1991 Wrangler 2.5L problem
 

Could you have 2 plug wires mixed or the wrong rotation on the
distributor cap?

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

dwd3773@bellsouth.net wrote:
>
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick

Re: 1991 Wrangler 2.5L problem
 

Could you have 2 plug wires mixed or the wrong rotation on the
distributor cap?

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

dwd3773@bellsouth.net wrote:
>
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick

Re: 1991 Wrangler 2.5L problem
 

Could you have 2 plug wires mixed or the wrong rotation on the
distributor cap?

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

dwd3773@bellsouth.net wrote:
>
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick

Re: 1991 Wrangler 2.5L problem
 

Weak coil or bad ignition wires or plugs. The back fire is raw gas
via a misfire pushed out into the exhaust for the next cylinder that
fired to ignite.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

dwd3773@bellsouth.net wrote:
>
> I have a 1991 Wrangler with a 2.5 liter fuel injected engine. I have
> been working on restoring it for a little while but now that I have it
> where I can drive it, I have a problem somewhere. I have no clue what
> or where the problem is. All I know is that when the engine is at an
> idle, it runs very smooth and sounds like a normal engine does. But
> when I try to drive it, it starts to backfire really bad, but as soon
> as I let off the gas it goes right back to that smooth idle. I have
> just about replaced everything in the engine compartment. This problem
> has really hendered my progress on getting my jeep road ready. If
> anyone can help please let me know. Also does anyone know what the fuel
> pressure is supposed to be on this engine?
>
> Thanks
> Derrick