97 TJ wont start
06-24-2006, 01:21 PM
#1
Guest
Posts: n/a
97 TJ wont start
My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
there were a couple of mornings when the idle was rough and I wuld have
to keep my foot in the gas a little to keep her going but after a bit it
would go fine. Then, last week at work, I started up and started to
back out when it stalled. I opened the hood and jiggled and banged on
everything I could see and checked all the fuses. Still nothing. Then
after about thirty minutes, it just started up and ran home. The next
day it wouldn't start and hasn't since. I noticed today that the fuel
pump is running constantly while the key is in the on position and there
is definitely fuel pressure at the rail. I pulled the coil wire and I'm
not getting any juice to the distributor. Anyways, after reading around
a little, i'm leaning to replacing the crank position sensor. Does
anyone have any additional advice? Could a malfunctioning CPS make the
brain think the fuel pump needs to run constantly? Any help is
appreciated....Rob
there were a couple of mornings when the idle was rough and I wuld have
to keep my foot in the gas a little to keep her going but after a bit it
would go fine. Then, last week at work, I started up and started to
back out when it stalled. I opened the hood and jiggled and banged on
everything I could see and checked all the fuses. Still nothing. Then
after about thirty minutes, it just started up and ran home. The next
day it wouldn't start and hasn't since. I noticed today that the fuel
pump is running constantly while the key is in the on position and there
is definitely fuel pressure at the rail. I pulled the coil wire and I'm
not getting any juice to the distributor. Anyways, after reading around
a little, i'm leaning to replacing the crank position sensor. Does
anyone have any additional advice? Could a malfunctioning CPS make the
brain think the fuel pump needs to run constantly? Any help is
appreciated....Rob
06-24-2006, 01:29 PM
#2
Guest
Posts: n/a
Re: 97 TJ wont start
rs wrote:
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
Sorry, I forgot to add that I tried to pull the codes by turning the
ignition on-off-on-off-on, but nothing happened...
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
Sorry, I forgot to add that I tried to pull the codes by turning the
ignition on-off-on-off-on, but nothing happened...
06-24-2006, 01:29 PM
#3
Guest
Posts: n/a
Re: 97 TJ wont start
rs wrote:
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
Sorry, I forgot to add that I tried to pull the codes by turning the
ignition on-off-on-off-on, but nothing happened...
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
Sorry, I forgot to add that I tried to pull the codes by turning the
ignition on-off-on-off-on, but nothing happened...
06-24-2006, 01:29 PM
#4
Guest
Posts: n/a
Re: 97 TJ wont start
rs wrote:
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
Sorry, I forgot to add that I tried to pull the codes by turning the
ignition on-off-on-off-on, but nothing happened...
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
Sorry, I forgot to add that I tried to pull the codes by turning the
ignition on-off-on-off-on, but nothing happened...
06-24-2006, 01:36 PM
#5
Guest
Posts: n/a
Re: 97 TJ wont start
I would start by using a spray contact cleaner or even WD40 on the
electrical connections for the TPS on the throttle body, then the CPS
plug for the flywheel one and the CPS plug for the distributor one.
My guess is the TPS connection...
One other thing that can cause something like that is the mesh strap
from the rear of the engine up to the firewall or it's connections. If
you live in the rust belt, these tend to fail early.
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)
rs wrote:
>
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
electrical connections for the TPS on the throttle body, then the CPS
plug for the flywheel one and the CPS plug for the distributor one.
My guess is the TPS connection...
One other thing that can cause something like that is the mesh strap
from the rear of the engine up to the firewall or it's connections. If
you live in the rust belt, these tend to fail early.
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)
rs wrote:
>
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
06-24-2006, 01:36 PM
#6
Guest
Posts: n/a
Re: 97 TJ wont start
I would start by using a spray contact cleaner or even WD40 on the
electrical connections for the TPS on the throttle body, then the CPS
plug for the flywheel one and the CPS plug for the distributor one.
My guess is the TPS connection...
One other thing that can cause something like that is the mesh strap
from the rear of the engine up to the firewall or it's connections. If
you live in the rust belt, these tend to fail early.
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)
rs wrote:
>
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
electrical connections for the TPS on the throttle body, then the CPS
plug for the flywheel one and the CPS plug for the distributor one.
My guess is the TPS connection...
One other thing that can cause something like that is the mesh strap
from the rear of the engine up to the firewall or it's connections. If
you live in the rust belt, these tend to fail early.
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)
rs wrote:
>
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
06-24-2006, 01:36 PM
#7
Guest
Posts: n/a
Re: 97 TJ wont start
I would start by using a spray contact cleaner or even WD40 on the
electrical connections for the TPS on the throttle body, then the CPS
plug for the flywheel one and the CPS plug for the distributor one.
My guess is the TPS connection...
One other thing that can cause something like that is the mesh strap
from the rear of the engine up to the firewall or it's connections. If
you live in the rust belt, these tend to fail early.
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)
rs wrote:
>
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
electrical connections for the TPS on the throttle body, then the CPS
plug for the flywheel one and the CPS plug for the distributor one.
My guess is the TPS connection...
One other thing that can cause something like that is the mesh strap
from the rear of the engine up to the firewall or it's connections. If
you live in the rust belt, these tend to fail early.
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)
rs wrote:
>
> My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this,
> there were a couple of mornings when the idle was rough and I wuld have
> to keep my foot in the gas a little to keep her going but after a bit it
> would go fine. Then, last week at work, I started up and started to
> back out when it stalled. I opened the hood and jiggled and banged on
> everything I could see and checked all the fuses. Still nothing. Then
> after about thirty minutes, it just started up and ran home. The next
> day it wouldn't start and hasn't since. I noticed today that the fuel
> pump is running constantly while the key is in the on position and there
> is definitely fuel pressure at the rail. I pulled the coil wire and I'm
> not getting any juice to the distributor. Anyways, after reading around
> a little, i'm leaning to replacing the crank position sensor. Does
> anyone have any additional advice? Could a malfunctioning CPS make the
> brain think the fuel pump needs to run constantly? Any help is
> appreciated....Rob
06-24-2006, 03:18 PM
#8
Guest
Posts: n/a
Re: 97 TJ wont start
Mike Romain did pass the time by typing:
> I would start by using a spray contact cleaner or even WD40 on the
> electrical connections for the TPS on the throttle body, then the CPS
> plug for the flywheel one and the CPS plug for the distributor one.
>
> My guess is the TPS connection...
That's usually the culprit.
> One other thing that can cause something like that is the mesh strap
> from the rear of the engine up to the firewall or it's connections. If
> you live in the rust belt, these tend to fail early.
That and a dead coil. Coils are cheap and even if it doesn't fix the
problem you now have a spare. Although on mine it usually fails to
start or bucks when the coil is going.
The ASD relay will remove power to the coil if the engine fails to start
in 2-3 revs or if there is no CPS sensor input for more than a couple of
seconds.
--
DougW
> I would start by using a spray contact cleaner or even WD40 on the
> electrical connections for the TPS on the throttle body, then the CPS
> plug for the flywheel one and the CPS plug for the distributor one.
>
> My guess is the TPS connection...
That's usually the culprit.
> One other thing that can cause something like that is the mesh strap
> from the rear of the engine up to the firewall or it's connections. If
> you live in the rust belt, these tend to fail early.
That and a dead coil. Coils are cheap and even if it doesn't fix the
problem you now have a spare. Although on mine it usually fails to
start or bucks when the coil is going.
The ASD relay will remove power to the coil if the engine fails to start
in 2-3 revs or if there is no CPS sensor input for more than a couple of
seconds.
--
DougW
06-24-2006, 03:18 PM
#9
Guest
Posts: n/a
Re: 97 TJ wont start
Mike Romain did pass the time by typing:
> I would start by using a spray contact cleaner or even WD40 on the
> electrical connections for the TPS on the throttle body, then the CPS
> plug for the flywheel one and the CPS plug for the distributor one.
>
> My guess is the TPS connection...
That's usually the culprit.
> One other thing that can cause something like that is the mesh strap
> from the rear of the engine up to the firewall or it's connections. If
> you live in the rust belt, these tend to fail early.
That and a dead coil. Coils are cheap and even if it doesn't fix the
problem you now have a spare. Although on mine it usually fails to
start or bucks when the coil is going.
The ASD relay will remove power to the coil if the engine fails to start
in 2-3 revs or if there is no CPS sensor input for more than a couple of
seconds.
--
DougW
> I would start by using a spray contact cleaner or even WD40 on the
> electrical connections for the TPS on the throttle body, then the CPS
> plug for the flywheel one and the CPS plug for the distributor one.
>
> My guess is the TPS connection...
That's usually the culprit.
> One other thing that can cause something like that is the mesh strap
> from the rear of the engine up to the firewall or it's connections. If
> you live in the rust belt, these tend to fail early.
That and a dead coil. Coils are cheap and even if it doesn't fix the
problem you now have a spare. Although on mine it usually fails to
start or bucks when the coil is going.
The ASD relay will remove power to the coil if the engine fails to start
in 2-3 revs or if there is no CPS sensor input for more than a couple of
seconds.
--
DougW
06-24-2006, 03:18 PM
#10
Guest
Posts: n/a
Re: 97 TJ wont start
Mike Romain did pass the time by typing:
> I would start by using a spray contact cleaner or even WD40 on the
> electrical connections for the TPS on the throttle body, then the CPS
> plug for the flywheel one and the CPS plug for the distributor one.
>
> My guess is the TPS connection...
That's usually the culprit.
> One other thing that can cause something like that is the mesh strap
> from the rear of the engine up to the firewall or it's connections. If
> you live in the rust belt, these tend to fail early.
That and a dead coil. Coils are cheap and even if it doesn't fix the
problem you now have a spare. Although on mine it usually fails to
start or bucks when the coil is going.
The ASD relay will remove power to the coil if the engine fails to start
in 2-3 revs or if there is no CPS sensor input for more than a couple of
seconds.
--
DougW
> I would start by using a spray contact cleaner or even WD40 on the
> electrical connections for the TPS on the throttle body, then the CPS
> plug for the flywheel one and the CPS plug for the distributor one.
>
> My guess is the TPS connection...
That's usually the culprit.
> One other thing that can cause something like that is the mesh strap
> from the rear of the engine up to the firewall or it's connections. If
> you live in the rust belt, these tend to fail early.
That and a dead coil. Coils are cheap and even if it doesn't fix the
problem you now have a spare. Although on mine it usually fails to
start or bucks when the coil is going.
The ASD relay will remove power to the coil if the engine fails to start
in 2-3 revs or if there is no CPS sensor input for more than a couple of
seconds.
--
DougW