"Brent Bogrees" <bogrees.1@osu.edu> wrote in message
news:6a04cef7.0404060526.2681e272@posting.google.c om...
> The first thing you should do is buy a code reader like you said. If
> the computer isn't bad, it will usually tell you what sensor is bad or
> if there is another problem. I had a similiar problem as you, and it
> turned out to be the CPS sensor. The only way I was able to determine
> this was with a code reader. But that isn't your problem because you
> are getting spark. Buy the code reader before you spend any more
> money..

You don't need a code reader on a '91. Turn the ignition on and off three
times in rapid succession and the codes will blink out with a pause between
each digit. the last code, indicating end of codes is 5-5.
http://www.sierrajeep.com/trouble.htm

Jeff Lowe
'91 YJ
'00 XJ

 

"Brent Bogrees" <bogrees.1@osu.edu> wrote in message
news:6a04cef7.0404060526.2681e272@posting.google.c om...
> The first thing you should do is buy a code reader like you said. If
> the computer isn't bad, it will usually tell you what sensor is bad or
> if there is another problem. I had a similiar problem as you, and it
> turned out to be the CPS sensor. The only way I was able to determine
> this was with a code reader. But that isn't your problem because you
> are getting spark. Buy the code reader before you spend any more
> money..

You don't need a code reader on a '91. Turn the ignition on and off three
times in rapid succession and the codes will blink out with a pause between
each digit. the last code, indicating end of codes is 5-5.
http://www.sierrajeep.com/trouble.htm

Jeff Lowe
'91 YJ
'00 XJ

 

"Brent Bogrees" <bogrees.1@osu.edu> wrote in message
news:6a04cef7.0404060526.2681e272@posting.google.c om...
> The first thing you should do is buy a code reader like you said. If
> the computer isn't bad, it will usually tell you what sensor is bad or
> if there is another problem. I had a similiar problem as you, and it
> turned out to be the CPS sensor. The only way I was able to determine
> this was with a code reader. But that isn't your problem because you
> are getting spark. Buy the code reader before you spend any more
> money..

You don't need a code reader on a '91. Turn the ignition on and off three
times in rapid succession and the codes will blink out with a pause between
each digit. the last code, indicating end of codes is 5-5.
http://www.sierrajeep.com/trouble.htm

Jeff Lowe
'91 YJ
'00 XJ

 

crank sensor??


"Jeff Lowe" <jalowe44.del.ete.this@hotmail..com.invaid> wrote in message
news:4CAcc.4920$1y1.1109@nwrdny03.gnilink.net...
>
> "Brent Bogrees" <bogrees.1@osu.edu> wrote in message
> news:6a04cef7.0404060526.2681e272@posting.google.c om...
> > The first thing you should do is buy a code reader like you said. If
> > the computer isn't bad, it will usually tell you what sensor is bad or
> > if there is another problem. I had a similiar problem as you, and it
> > turned out to be the CPS sensor. The only way I was able to determine
> > this was with a code reader. But that isn't your problem because you
> > are getting spark. Buy the code reader before you spend any more
> > money..
>
> You don't need a code reader on a '91. Turn the ignition on and off three
> times in rapid succession and the codes will blink out with a pause
between
> each digit. the last code, indicating end of codes is 5-5.
> http://www.sierrajeep.com/trouble.htm
>
> Jeff Lowe
> '91 YJ
> '00 XJ
>
>

 

crank sensor??


"Jeff Lowe" <jalowe44.del.ete.this@hotmail..com.invaid> wrote in message
news:4CAcc.4920$1y1.1109@nwrdny03.gnilink.net...
>
> "Brent Bogrees" <bogrees.1@osu.edu> wrote in message
> news:6a04cef7.0404060526.2681e272@posting.google.c om...
> > The first thing you should do is buy a code reader like you said. If
> > the computer isn't bad, it will usually tell you what sensor is bad or
> > if there is another problem. I had a similiar problem as you, and it
> > turned out to be the CPS sensor. The only way I was able to determine
> > this was with a code reader. But that isn't your problem because you
> > are getting spark. Buy the code reader before you spend any more
> > money..
>
> You don't need a code reader on a '91. Turn the ignition on and off three
> times in rapid succession and the codes will blink out with a pause
between
> each digit. the last code, indicating end of codes is 5-5.
> http://www.sierrajeep.com/trouble.htm
>
> Jeff Lowe
> '91 YJ
> '00 XJ
>
>

 

crank sensor??


"Jeff Lowe" <jalowe44.del.ete.this@hotmail..com.invaid> wrote in message
news:4CAcc.4920$1y1.1109@nwrdny03.gnilink.net...
>
> "Brent Bogrees" <bogrees.1@osu.edu> wrote in message
> news:6a04cef7.0404060526.2681e272@posting.google.c om...
> > The first thing you should do is buy a code reader like you said. If
> > the computer isn't bad, it will usually tell you what sensor is bad or
> > if there is another problem. I had a similiar problem as you, and it
> > turned out to be the CPS sensor. The only way I was able to determine
> > this was with a code reader. But that isn't your problem because you
> > are getting spark. Buy the code reader before you spend any more
> > money..
>
> You don't need a code reader on a '91. Turn the ignition on and off three
> times in rapid succession and the codes will blink out with a pause
between
> each digit. the last code, indicating end of codes is 5-5.
> http://www.sierrajeep.com/trouble.htm
>
> Jeff Lowe
> '91 YJ
> '00 XJ
>
>

 

crank sensor??


"Jeff Lowe" <jalowe44.del.ete.this@hotmail..com.invaid> wrote in message
news:4CAcc.4920$1y1.1109@nwrdny03.gnilink.net...
>
> "Brent Bogrees" <bogrees.1@osu.edu> wrote in message
> news:6a04cef7.0404060526.2681e272@posting.google.c om...
> > The first thing you should do is buy a code reader like you said. If
> > the computer isn't bad, it will usually tell you what sensor is bad or
> > if there is another problem. I had a similiar problem as you, and it
> > turned out to be the CPS sensor. The only way I was able to determine
> > this was with a code reader. But that isn't your problem because you
> > are getting spark. Buy the code reader before you spend any more
> > money..
>
> You don't need a code reader on a '91. Turn the ignition on and off three
> times in rapid succession and the codes will blink out with a pause
between
> each digit. the last code, indicating end of codes is 5-5.
> http://www.sierrajeep.com/trouble.htm
>
> Jeff Lowe
> '91 YJ
> '00 XJ
>
>

 

(CPS) Crankshaft Position Sensor, which counts
the flywheel teeth and is mounted on the bell housing......
Just my thoughts, as mentioned in a previous post.

Paul in VA

"mike" <mcapsu@yahoo.com> wrote in message
news:fed0233a.0404052134.6838cdcf@posting.google.c om...
> I am going nuts with this problem,
>
> my 91 yj has not started in about six months now!
>
> I changed the oil around october and parked it for a week, then went
> to start it up and it cranked and cranked, but didnt start.
>
> Now the list starts...
>
> fuel filter? changed it no help
>
> fuel pump? got a fuel pressure gauge and the fuel rail has pressure
> within spec (36-40 psi)
>
> spark? put a timing light on it, i have spark on all 4 plugs
>
> not enough spark?
> changed plugs, wires, cap, rotor, coil
>
> injectors not opening?
> bought a set of noid lights and they blink like a christmas tree like
> they are supposed to, and the plugs are wet, pulled injectors and
> replaced o-rings and cleaned as best i could by hand, I couldnt find a
> place that would test them to see if they were stuck open
>
> out of time?
> put the light on it and cranked it over... looked to be 4 degrees
> retarded... changed timing chain(which was a bit slack when i took the
> cover off), sprockets and tensioner and noticed the water pump was
> leaking, changed that too, now its fireing at 0
>
> electrical?
> checked ground strap from block to firewall for continuity - very low
> to no resistance, same with negative post of battery to block or
> chassis
> fuses - all look good, under hood and under dash
>
> bad gas?
> siphoned out tank and refilled, cranked a bunch with the release of
> the fuel pressure gauge open to get the gas in the lines 'clean'
>
> i am stumped, i guess im back to electrical, i just pulled all of the
> underdash fuses except the ignition fuse, it cranks and sounds like
> maybe one cylinder is fireing(same as with them all in), my next todos
> are to get a code reader and see if i get anything on that, then also
> check the ground to the coil, then maybe replace the computer...
>
> does anyone know where the computer is located on a '91 yj 2.5l?
> can they test that out of the vehicle?
>
> i cant seem to find a timing setting on it, is it supposed to fire
> advanced at all? or is that controlled by the computer?
>
> also all the dash gauges/idiot lights are now not coming on (yes with
> the fuses in, no check engine light earlier in the disaster which is
> why i didnt hook up an OBD reader earlier)
>
> compression? (i would have thought id get more warning on this? it is
> a 2.5l turning 31s so it was never peppy)
>
> any other ideas?
>
> sorry if this post sounds a bit angry but im just frustrated, thanks
> for any help in advance
>
> Thanks,
> Mike
>
> 96xj (luckily this one is hauling me around trustilly)
> 91yj (lets pull it out of its early grave!)
> 97 ducati monster 900 (new toy :-) )

 

(CPS) Crankshaft Position Sensor, which counts
the flywheel teeth and is mounted on the bell housing......
Just my thoughts, as mentioned in a previous post.

Paul in VA

"mike" <mcapsu@yahoo.com> wrote in message
news:fed0233a.0404052134.6838cdcf@posting.google.c om...
> I am going nuts with this problem,
>
> my 91 yj has not started in about six months now!
>
> I changed the oil around october and parked it for a week, then went
> to start it up and it cranked and cranked, but didnt start.
>
> Now the list starts...
>
> fuel filter? changed it no help
>
> fuel pump? got a fuel pressure gauge and the fuel rail has pressure
> within spec (36-40 psi)
>
> spark? put a timing light on it, i have spark on all 4 plugs
>
> not enough spark?
> changed plugs, wires, cap, rotor, coil
>
> injectors not opening?
> bought a set of noid lights and they blink like a christmas tree like
> they are supposed to, and the plugs are wet, pulled injectors and
> replaced o-rings and cleaned as best i could by hand, I couldnt find a
> place that would test them to see if they were stuck open
>
> out of time?
> put the light on it and cranked it over... looked to be 4 degrees
> retarded... changed timing chain(which was a bit slack when i took the
> cover off), sprockets and tensioner and noticed the water pump was
> leaking, changed that too, now its fireing at 0
>
> electrical?
> checked ground strap from block to firewall for continuity - very low
> to no resistance, same with negative post of battery to block or
> chassis
> fuses - all look good, under hood and under dash
>
> bad gas?
> siphoned out tank and refilled, cranked a bunch with the release of
> the fuel pressure gauge open to get the gas in the lines 'clean'
>
> i am stumped, i guess im back to electrical, i just pulled all of the
> underdash fuses except the ignition fuse, it cranks and sounds like
> maybe one cylinder is fireing(same as with them all in), my next todos
> are to get a code reader and see if i get anything on that, then also
> check the ground to the coil, then maybe replace the computer...
>
> does anyone know where the computer is located on a '91 yj 2.5l?
> can they test that out of the vehicle?
>
> i cant seem to find a timing setting on it, is it supposed to fire
> advanced at all? or is that controlled by the computer?
>
> also all the dash gauges/idiot lights are now not coming on (yes with
> the fuses in, no check engine light earlier in the disaster which is
> why i didnt hook up an OBD reader earlier)
>
> compression? (i would have thought id get more warning on this? it is
> a 2.5l turning 31s so it was never peppy)
>
> any other ideas?
>
> sorry if this post sounds a bit angry but im just frustrated, thanks
> for any help in advance
>
> Thanks,
> Mike
>
> 96xj (luckily this one is hauling me around trustilly)
> 91yj (lets pull it out of its early grave!)
> 97 ducati monster 900 (new toy :-) )

 

(CPS) Crankshaft Position Sensor, which counts
the flywheel teeth and is mounted on the bell housing......
Just my thoughts, as mentioned in a previous post.

Paul in VA

"mike" <mcapsu@yahoo.com> wrote in message
news:fed0233a.0404052134.6838cdcf@posting.google.c om...
> I am going nuts with this problem,
>
> my 91 yj has not started in about six months now!
>
> I changed the oil around october and parked it for a week, then went
> to start it up and it cranked and cranked, but didnt start.
>
> Now the list starts...
>
> fuel filter? changed it no help
>
> fuel pump? got a fuel pressure gauge and the fuel rail has pressure
> within spec (36-40 psi)
>
> spark? put a timing light on it, i have spark on all 4 plugs
>
> not enough spark?
> changed plugs, wires, cap, rotor, coil
>
> injectors not opening?
> bought a set of noid lights and they blink like a christmas tree like
> they are supposed to, and the plugs are wet, pulled injectors and
> replaced o-rings and cleaned as best i could by hand, I couldnt find a
> place that would test them to see if they were stuck open
>
> out of time?
> put the light on it and cranked it over... looked to be 4 degrees
> retarded... changed timing chain(which was a bit slack when i took the
> cover off), sprockets and tensioner and noticed the water pump was
> leaking, changed that too, now its fireing at 0
>
> electrical?
> checked ground strap from block to firewall for continuity - very low
> to no resistance, same with negative post of battery to block or
> chassis
> fuses - all look good, under hood and under dash
>
> bad gas?
> siphoned out tank and refilled, cranked a bunch with the release of
> the fuel pressure gauge open to get the gas in the lines 'clean'
>
> i am stumped, i guess im back to electrical, i just pulled all of the
> underdash fuses except the ignition fuse, it cranks and sounds like
> maybe one cylinder is fireing(same as with them all in), my next todos
> are to get a code reader and see if i get anything on that, then also
> check the ground to the coil, then maybe replace the computer...
>
> does anyone know where the computer is located on a '91 yj 2.5l?
> can they test that out of the vehicle?
>
> i cant seem to find a timing setting on it, is it supposed to fire
> advanced at all? or is that controlled by the computer?
>
> also all the dash gauges/idiot lights are now not coming on (yes with
> the fuses in, no check engine light earlier in the disaster which is
> why i didnt hook up an OBD reader earlier)
>
> compression? (i would have thought id get more warning on this? it is
> a 2.5l turning 31s so it was never peppy)
>
> any other ideas?
>
> sorry if this post sounds a bit angry but im just frustrated, thanks
> for any help in advance
>
> Thanks,
> Mike
>
> 96xj (luckily this one is hauling me around trustilly)
> 91yj (lets pull it out of its early grave!)
> 97 ducati monster 900 (new toy :-) )