I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
couple of questions. The indidivual that I got it from said the 4wd
was not currently working and when I had a friend take a look at it we
were kind of noticing that all the vacuum tubes/connections had been
removed. Is there any complete diagrams that would show in detail the
4wd vacuum system so I can get a good list of parts and be able to set
it back up? They also replaced the air cleaner (with a simple air
filter) and if there are some good diagrams on that I would greatly
appreciate it as well since I believe there are a couple of connections
off of there I will be needing. I have purchased a Chilton book but it
doesn't really get into the 4wd stuff and the vacuum diagrams in there
are desciptive but still hard to read for a newbie. Any help or
direction to a site or place that I could get the 4wd reconstruction
for dumbies would be helpful.

Thanks in advance.

D

 

They sell the kit at the Stealership for around twenty:
http://www.----------.com/axleVacDiagram.jpg
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

NewbieJeepGuy wrote:
>
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D

 

They sell the kit at the Stealership for around twenty:
http://www.----------.com/axleVacDiagram.jpg
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

NewbieJeepGuy wrote:
>
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D

 

They sell the kit at the Stealership for around twenty:
http://www.----------.com/axleVacDiagram.jpg
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

NewbieJeepGuy wrote:
>
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D

 

For a good look at all the vacumn lines for the engine, start here:
http://home.sprynet.com/~dale02/list.htm

The front axle disconnect system does not seem to be well documented.
There is a black plastic line from the driver's side of the engine to
the vac switch located on top of the transfercase. Then 3 lines going to
the vac motor on the axle. Take a look at the vac motor on the axle, see
if it still has the molded plug attached to the vac ports. With the
engine running, tranny in neutral, transfer case in 2wd, CAREFULLy reach
down to the front axle molded plug and see if you have slight vac on the
yellow line, move it to 4wd, see if you have slight vac on green line.
If no vac on either, you have a bad line going from the engine to the
transfer case. If either green or yellow and doesn't switch, bad vac
switch. If vac on one, no vac on the other, probably a bad vac harness.

A lot of folks will tell you to replace the vac system with a cable, not
a bad option. I stuck with the vac system since I switch from 2WD to 4WD
a lot.

Part numbers you may need:

vac harness (complete) 5300-2033 About $75 new at the dealer only
vac switch 5300-1101

If you post a valid e-mail address, I'll send you some diagrams.

NewbieJeepGuy wrote:
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D
>

 

For a good look at all the vacumn lines for the engine, start here:
http://home.sprynet.com/~dale02/list.htm

The front axle disconnect system does not seem to be well documented.
There is a black plastic line from the driver's side of the engine to
the vac switch located on top of the transfercase. Then 3 lines going to
the vac motor on the axle. Take a look at the vac motor on the axle, see
if it still has the molded plug attached to the vac ports. With the
engine running, tranny in neutral, transfer case in 2wd, CAREFULLy reach
down to the front axle molded plug and see if you have slight vac on the
yellow line, move it to 4wd, see if you have slight vac on green line.
If no vac on either, you have a bad line going from the engine to the
transfer case. If either green or yellow and doesn't switch, bad vac
switch. If vac on one, no vac on the other, probably a bad vac harness.

A lot of folks will tell you to replace the vac system with a cable, not
a bad option. I stuck with the vac system since I switch from 2WD to 4WD
a lot.

Part numbers you may need:

vac harness (complete) 5300-2033 About $75 new at the dealer only
vac switch 5300-1101

If you post a valid e-mail address, I'll send you some diagrams.

NewbieJeepGuy wrote:
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D
>

 

For a good look at all the vacumn lines for the engine, start here:
http://home.sprynet.com/~dale02/list.htm

The front axle disconnect system does not seem to be well documented.
There is a black plastic line from the driver's side of the engine to
the vac switch located on top of the transfercase. Then 3 lines going to
the vac motor on the axle. Take a look at the vac motor on the axle, see
if it still has the molded plug attached to the vac ports. With the
engine running, tranny in neutral, transfer case in 2wd, CAREFULLy reach
down to the front axle molded plug and see if you have slight vac on the
yellow line, move it to 4wd, see if you have slight vac on green line.
If no vac on either, you have a bad line going from the engine to the
transfer case. If either green or yellow and doesn't switch, bad vac
switch. If vac on one, no vac on the other, probably a bad vac harness.

A lot of folks will tell you to replace the vac system with a cable, not
a bad option. I stuck with the vac system since I switch from 2WD to 4WD
a lot.

Part numbers you may need:

vac harness (complete) 5300-2033 About $75 new at the dealer only
vac switch 5300-1101

If you post a valid e-mail address, I'll send you some diagrams.

NewbieJeepGuy wrote:
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D
>

 

This site might help you out some:
http://home.sprynet.com/~dale02/list.htm

The Haynes 'CJ' manual is the best one to have for your engine and it's
electrics. That book has great detail on the 258.

If all the vacuum lines are off, then the computer will have gone into
'limp home' mode clamping down on the timing and carb mix and the engine
will run like a bag of dirt.

If you want to put it all back stock, see the link I posted above.

If you want to put the computer out of your misery it can be done by
simply adding two new wires and hooking the orange and purple wires at
the ignition module to the orange and purple at the distributor.
http://home.sprynet.com/~dale02/ignmods.htm

You then need to set the timing manually and set the carb mix up
manually. The carb does have mix screws hidden down front that might
need a drill or saw to get at. When setting up the mix, I believe the
stepper motor's pins should be in the middle of their travel where they
work stock to get the proper high speed running.

The computer bypass is called the 'Nutter' after the gent that posted
it. He set his carb pins full rich. This give lousy gas mileage and
top end performance. You can try both. I can adjust my carb pins from
up top with needle nose pliers or a mini screwdriver.

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)

NewbieJeepGuy wrote:
>
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D

 

This site might help you out some:
http://home.sprynet.com/~dale02/list.htm

The Haynes 'CJ' manual is the best one to have for your engine and it's
electrics. That book has great detail on the 258.

If all the vacuum lines are off, then the computer will have gone into
'limp home' mode clamping down on the timing and carb mix and the engine
will run like a bag of dirt.

If you want to put it all back stock, see the link I posted above.

If you want to put the computer out of your misery it can be done by
simply adding two new wires and hooking the orange and purple wires at
the ignition module to the orange and purple at the distributor.
http://home.sprynet.com/~dale02/ignmods.htm

You then need to set the timing manually and set the carb mix up
manually. The carb does have mix screws hidden down front that might
need a drill or saw to get at. When setting up the mix, I believe the
stepper motor's pins should be in the middle of their travel where they
work stock to get the proper high speed running.

The computer bypass is called the 'Nutter' after the gent that posted
it. He set his carb pins full rich. This give lousy gas mileage and
top end performance. You can try both. I can adjust my carb pins from
up top with needle nose pliers or a mini screwdriver.

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)

NewbieJeepGuy wrote:
>
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D

 

This site might help you out some:
http://home.sprynet.com/~dale02/list.htm

The Haynes 'CJ' manual is the best one to have for your engine and it's
electrics. That book has great detail on the 258.

If all the vacuum lines are off, then the computer will have gone into
'limp home' mode clamping down on the timing and carb mix and the engine
will run like a bag of dirt.

If you want to put it all back stock, see the link I posted above.

If you want to put the computer out of your misery it can be done by
simply adding two new wires and hooking the orange and purple wires at
the ignition module to the orange and purple at the distributor.
http://home.sprynet.com/~dale02/ignmods.htm

You then need to set the timing manually and set the carb mix up
manually. The carb does have mix screws hidden down front that might
need a drill or saw to get at. When setting up the mix, I believe the
stepper motor's pins should be in the middle of their travel where they
work stock to get the proper high speed running.

The computer bypass is called the 'Nutter' after the gent that posted
it. He set his carb pins full rich. This give lousy gas mileage and
top end performance. You can try both. I can adjust my carb pins from
up top with needle nose pliers or a mini screwdriver.

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)

NewbieJeepGuy wrote:
>
> I just bought a 1990 Jeep Wrangler with the 258 I6, 4wd and have a
> couple of questions. The indidivual that I got it from said the 4wd
> was not currently working and when I had a friend take a look at it we
> were kind of noticing that all the vacuum tubes/connections had been
> removed. Is there any complete diagrams that would show in detail the
> 4wd vacuum system so I can get a good list of parts and be able to set
> it back up? They also replaced the air cleaner (with a simple air
> filter) and if there are some good diagrams on that I would greatly
> appreciate it as well since I believe there are a couple of connections
> off of there I will be needing. I have purchased a Chilton book but it
> doesn't really get into the 4wd stuff and the vacuum diagrams in there
> are desciptive but still hard to read for a newbie. Any help or
> direction to a site or place that I could get the 4wd reconstruction
> for dumbies would be helpful.
>
> Thanks in advance.
>
> D