Still having high idle problem on 88 Jeep Comanche (4.0l)

#21

I've got some contact cleaner, as well as some WD40. I'll maybe give that a
whirl.

As far as suppliers goes, that's the kind of price I was hoping/expecting.
But apparently up here in Canada, they make them things out of gold. On the
plus side, if I find an old Jeep, I'm pretty sure I can haul that piece off
in about 2 minutes!

I'm getting very intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote

Quote:

Clint wrote:

So I stopped by the local parts place, and they wanted $280 for the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the two.
*sigh* I thought the automatic one had an extra electrical connector
on it? So shouldn't it be the more expensive of the two? Ah, well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic transmission
version in stock, but it was still $75, which seems pretty steep for a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity of $75
for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray it well
with WD40 or contact cleaner. You should be able to get some to filter
inside. Get as close to the unit as possible and measure the resistance
between all the pins. That !!@#$% thing is a simple rheostat so if you
turn it as far as it goes in one direction, you should get several ohms
(not sure of the exact value - sorry) between one of the pins and the
other
two. Leave one end of the ohm meter where it was and turn the thing about
half way. Now you should see about half the resistance at one of the
pins.
Swap thing around to be sure you have contact between all 3 pins at some
point. I have been able to clean the wiper arm in a couple of them by
soaking the thing in WD40 for a days or so - the shaft is not sealed, so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#22

If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter into
the back side of the plug and take a voltage reading. With the throttle
at rest, the volts should be 200 MV. At wide open, the volts should be
4.8V max. They should smoothly increase as the throttle opens.

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)

Clint wrote:

Quote:

I've got some contact cleaner, as well as some WD40. I'll maybe give
that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make them
things out of gold. On the plus side, if I find an old Jeep, I'm pretty
sure I can haul that piece off in about 2 minutes!

I'm getting very
intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the two.
*sigh* I thought the automatic one had an extra electrical connector
on it? So shouldn't it be the more expensive of the two? Ah, well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic transmission
version in stock, but it was still $75, which seems pretty steep for a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity of
$75 for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray it well
with WD40 or contact cleaner. You should be able to get some to filter
inside. Get as close to the unit as possible and measure the resistance
between all the pins. That !!@#$% thing is a simple rheostat so if you
turn it as far as it goes in one direction, you should get several ohms
(not sure of the exact value - sorry) between one of the pins and the
other
two. Leave one end of the ohm meter where it was and turn the thing
about
half way. Now you should see about half the resistance at one of the
pins.
Swap thing around to be sure you have contact between all 3 pins at some
point. I have been able to clean the wiper arm in a couple of them by
soaking the thing in WD40 for a days or so - the shaft is not sealed, so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and
Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#23

To go off on a (yet another) small tangent, is there a way to test the IAS
to make sure it's working correctly?

BTW, I took off the TPS, and tested the resistance as it rotated through
it's range. But without having a known good one, all I can say is that it
does go through a range of resistances smoothly.

I also learned something today, and I'm going to post it in the interest of
assisting others. Otherwise I'd just hide my red face behind the computer
screen. When putting the TPS on, the default position seemed to have the
lever arm on the wrong side of the throttle body arm. This would cause the
TPS to be rendered pretty much useless, as far as I can see, as it won't
move with the throttle body lever. Whoops. So just watch that if you need
to replace/adjust that.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote

Quote:

If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter into the
back side of the plug and take a voltage reading. With the throttle at
rest, the volts should be 200 MV. At wide open, the volts should be 4.8V
max. They should smoothly increase as the throttle opens.

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)

Clint wrote:
I've got some contact cleaner, as well as some WD40. I'll maybe give
that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make them things
out of gold. On the plus side, if I find an old Jeep, I'm pretty sure I
can haul that piece off in about 2 minutes!

I'm getting very intimate
with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the two.
*sigh* I thought the automatic one had an extra electrical connector
on it? So shouldn't it be the more expensive of the two? Ah, well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic transmission
version in stock, but it was still $75, which seems pretty steep for a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity of $75
for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray it well
with WD40 or contact cleaner. You should be able to get some to filter
inside. Get as close to the unit as possible and measure the resistance
between all the pins. That !!@#$% thing is a simple rheostat so if you
turn it as far as it goes in one direction, you should get several ohms
(not sure of the exact value - sorry) between one of the pins and the
other
two. Leave one end of the ohm meter where it was and turn the thing
about
half way. Now you should see about half the resistance at one of the
pins.
Swap thing around to be sure you have contact between all 3 pins at some
point. I have been able to clean the wiper arm in a couple of them by
soaking the thing in WD40 for a days or so - the shaft is not sealed,
so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and
Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#24

Does your meter not have a volt setting?

Mike

Clint wrote:

Quote:

To go off on a (yet another) small tangent, is there a way to test the
IAS to make sure it's working correctly?

BTW, I took off the TPS, and tested the resistance as it rotated through
it's range. But without having a known good one, all I can say is that
it does go through a range of resistances smoothly.

I also learned something today, and I'm going to post it in the interest
of assisting others. Otherwise I'd just hide my red face behind the
computer screen. When putting the TPS on, the default position seemed
to have the lever arm on the wrong side of the throttle body arm. This
would cause the TPS to be rendered pretty much useless, as far as I can
see, as it won't move with the throttle body lever. Whoops. So just
watch that if you need to replace/adjust that.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612802a$0$6626$9a6e19ea (AT) unlimited (DOT) newshosting.com...
If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter into
the back side of the plug and take a voltage reading. With the
throttle at rest, the volts should be 200 MV. At wide open, the volts
should be 4.8V max. They should smoothly increase as the throttle opens.

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)

Clint wrote:
I've got some contact cleaner, as well as some WD40. I'll maybe give
that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make them
things out of gold. On the plus side, if I find an old Jeep, I'm
pretty sure I can haul that piece off in about 2 minutes!

I'm
getting very intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the two.
*sigh* I thought the automatic one had an extra electrical connector
on it? So shouldn't it be the more expensive of the two? Ah, well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic transmission
version in stock, but it was still $75, which seems pretty steep for a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity of
$75 for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray it
well
with WD40 or contact cleaner. You should be able to get some to filter
inside. Get as close to the unit as possible and measure the
resistance
between all the pins. That !!@#$% thing is a simple rheostat so if you
turn it as far as it goes in one direction, you should get several ohms
(not sure of the exact value - sorry) between one of the pins and
the other
two. Leave one end of the ohm meter where it was and turn the thing
about
half way. Now you should see about half the resistance at one of
the pins.
Swap thing around to be sure you have contact between all 3 pins at
some
point. I have been able to clean the wiper arm in a couple of them by
soaking the thing in WD40 for a days or so - the shaft is not
sealed, so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and
Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#25

I measured before, and was getting < .5V. But whether it was exactly .2V or
not, my meter didn't give me confidence enough to say yeah or nay.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote

Quote:

Does your meter not have a volt setting?

Mike

Clint wrote:
To go off on a (yet another) small tangent, is there a way to test the
IAS to make sure it's working correctly?

BTW, I took off the TPS, and tested the resistance as it rotated through
it's range. But without having a known good one, all I can say is that
it does go through a range of resistances smoothly.

I also learned something today, and I'm going to post it in the interest
of assisting others. Otherwise I'd just hide my red face behind the
computer screen. When putting the TPS on, the default position seemed to
have the lever arm on the wrong side of the throttle body arm. This
would cause the TPS to be rendered pretty much useless, as far as I can
see, as it won't move with the throttle body lever. Whoops. So just
watch that if you need to replace/adjust that.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612802a$0$6626$9a6e19ea (AT) unlimited (DOT) newshosting.com...
If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter into
the back side of the plug and take a voltage reading. With the throttle
at rest, the volts should be 200 MV. At wide open, the volts should be
4.8V max. They should smoothly increase as the throttle opens.

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)

Clint wrote:
I've got some contact cleaner, as well as some WD40. I'll maybe give
that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make them
things out of gold. On the plus side, if I find an old Jeep, I'm
pretty sure I can haul that piece off in about 2 minutes!

I'm
getting very intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the two.
*sigh* I thought the automatic one had an extra electrical connector
on it? So shouldn't it be the more expensive of the two? Ah, well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic transmission
version in stock, but it was still $75, which seems pretty steep for
a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity of
$75 for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray it
well
with WD40 or contact cleaner. You should be able to get some to
filter
inside. Get as close to the unit as possible and measure the
resistance
between all the pins. That !!@#$% thing is a simple rheostat so if
you
turn it as far as it goes in one direction, you should get several
ohms
(not sure of the exact value - sorry) between one of the pins and the
other
two. Leave one end of the ohm meter where it was and turn the thing
about
half way. Now you should see about half the resistance at one of the
pins.
Swap thing around to be sure you have contact between all 3 pins at
some
point. I have been able to clean the wiper arm in a couple of them by
soaking the thing in WD40 for a days or so - the shaft is not sealed,
so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and
Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#26

There is a special tool my book calls an 'exerciser' to test the idle
stepper. The book sort of implies a high moves the pintle out and a low
in, but it doesn't say for sure.

It, the ISS has a moving part that can stand to be cleaned.

Mike

Clint wrote:

Quote:

I measured before, and was getting < .5V. But whether it was exactly
.2V or not, my meter didn't give me confidence enough to say yeah or nay.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612b0c8$0$2948$9a6e19ea (AT) unlimited (DOT) newshosting.com...
Does your meter not have a volt setting?

Mike

Clint wrote:
To go off on a (yet another) small tangent, is there a way to test
the IAS to make sure it's working correctly?

BTW, I took off the TPS, and tested the resistance as it rotated
through it's range. But without having a known good one, all I can
say is that it does go through a range of resistances smoothly.

I also learned something today, and I'm going to post it in the
interest of assisting others. Otherwise I'd just hide my red face
behind the computer screen. When putting the TPS on, the default
position seemed to have the lever arm on the wrong side of the
throttle body arm. This would cause the TPS to be rendered pretty
much useless, as far as I can see, as it won't move with the throttle
body lever. Whoops. So just watch that if you need to
replace/adjust that.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612802a$0$6626$9a6e19ea (AT) unlimited (DOT) newshosting.com...
If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter
into the back side of the plug and take a voltage reading. With the
throttle at rest, the volts should be 200 MV. At wide open, the
volts should be 4.8V max. They should smoothly increase as the
throttle opens.

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)

Clint wrote:
I've got some contact cleaner, as well as some WD40. I'll maybe
give that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make them
things out of gold. On the plus side, if I find an old Jeep, I'm
pretty sure I can haul that piece off in about 2 minutes!

I'm
getting very intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the
two.
*sigh* I thought the automatic one had an extra electrical
connector
on it? So shouldn't it be the more expensive of the two? Ah, well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic
transmission
version in stock, but it was still $75, which seems pretty steep
for a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity
of $75 for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray
it well
with WD40 or contact cleaner. You should be able to get some to
filter
inside. Get as close to the unit as possible and measure the
resistance
between all the pins. That !!@#$% thing is a simple rheostat so
if you
turn it as far as it goes in one direction, you should get several
ohms
(not sure of the exact value - sorry) between one of the pins and
the other
two. Leave one end of the ohm meter where it was and turn the
thing about
half way. Now you should see about half the resistance at one of
the pins.
Swap thing around to be sure you have contact between all 3 pins
at some
point. I have been able to clean the wiper arm in a couple of
them by
soaking the thing in WD40 for a days or so - the shaft is not
sealed, so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and
Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#27

Mike Romain wrote:

Quote:

There is a special tool my book calls an 'exerciser' to test the idle
stepper. The book sort of implies a high moves the pintle out and a
low in, but it doesn't say for sure.

It, the ISS has a moving part that can stand to be cleaned.

Be careful. Never start the engine with the IAS motor removed or the
little pintle will shoot across the garage and the unit is toast.

With the ignition on, motor not running.

back-probe the connector and find the ground and +5v
(should be the outside two wires)
If there isn't 5v there then you might have a break in the harness
or just not a good contact with the wire.
Now measure the center wire against the ground.

Throttle butterfly Voltage
CLOSED >200 mV
OPEN <4.8 V

The transition between full open and closed should be smooth
with no jumps or dropouts.

--
DougW

#28

So I went out to a local wrecker, and they had about 6 Cherokee's, all of
about the right vintage. 3 of them still had their IAC's, but all of them
were automatic's, so I couldn't yank the TPS's. Kind of disappointed by the
lack of selection on those.

Anyway, the "new" IAC only cost $2 (the entire throttle body with add-ons
was only $20), but it had exactly the same effect as the old one. *sigh* So
I'm still looking for a TPS to plug in there.

Anyone know if the automatic tranny version of the sensor has any hope of
working? Or would I just be asking for even more pain?

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote

Quote:

There is a special tool my book calls an 'exerciser' to test the idle
stepper. The book sort of implies a high moves the pintle out and a low
in, but it doesn't say for sure.

It, the ISS has a moving part that can stand to be cleaned.

Mike

Clint wrote:
I measured before, and was getting < .5V. But whether it was exactly .2V
or not, my meter didn't give me confidence enough to say yeah or nay.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612b0c8$0$2948$9a6e19ea (AT) unlimited (DOT) newshosting.com...
Does your meter not have a volt setting?

Mike

Clint wrote:
To go off on a (yet another) small tangent, is there a way to test the
IAS to make sure it's working correctly?

BTW, I took off the TPS, and tested the resistance as it rotated
through it's range. But without having a known good one, all I can say
is that it does go through a range of resistances smoothly.

I also learned something today, and I'm going to post it in the
interest of assisting others. Otherwise I'd just hide my red face
behind the computer screen. When putting the TPS on, the default
position seemed to have the lever arm on the wrong side of the throttle
body arm. This would cause the TPS to be rendered pretty much useless,
as far as I can see, as it won't move with the throttle body lever.
Whoops. So just watch that if you need to replace/adjust that.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612802a$0$6626$9a6e19ea (AT) unlimited (DOT) newshosting.com...
If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter into
the back side of the plug and take a voltage reading. With the
throttle at rest, the volts should be 200 MV. At wide open, the volts
should be 4.8V max. They should smoothly increase as the throttle
opens.

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)

Clint wrote:
I've got some contact cleaner, as well as some WD40. I'll maybe give
that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make them
things out of gold. On the plus side, if I find an old Jeep, I'm
pretty sure I can haul that piece off in about 2 minutes!

I'm
getting very intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the
two.
*sigh* I thought the automatic one had an extra electrical
connector
on it? So shouldn't it be the more expensive of the two? Ah,
well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic
transmission
version in stock, but it was still $75, which seems pretty steep
for a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity of
$75 for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray it
well
with WD40 or contact cleaner. You should be able to get some to
filter
inside. Get as close to the unit as possible and measure the
resistance
between all the pins. That !!@#$% thing is a simple rheostat so if
you
turn it as far as it goes in one direction, you should get several
ohms
(not sure of the exact value - sorry) between one of the pins and
the other
two. Leave one end of the ohm meter where it was and turn the thing
about
half way. Now you should see about half the resistance at one of
the pins.
Swap thing around to be sure you have contact between all 3 pins at
some
point. I have been able to clean the wiper arm in a couple of them
by
soaking the thing in WD40 for a days or so - the shaft is not
sealed, so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and
Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#29

Now I am more thinking you are missing something... CCV unplugged or
one of the lines to the air filter box. There is one way down low in
the front by the rad that controls the heat pipe for the air filter.

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)

Clint wrote:

Quote:

So I went out to a local wrecker, and they had about 6 Cherokee's, all
of about the right vintage. 3 of them still had their IAC's, but all of
them were automatic's, so I couldn't yank the TPS's. Kind of
disappointed by the lack of selection on those.

Anyway, the "new" IAC only cost $2 (the entire throttle body with
add-ons was only $20), but it had exactly the same effect as the old
one. *sigh* So I'm still looking for a TPS to plug in there.

Anyone know if the automatic tranny version of the sensor has any hope
of working? Or would I just be asking for even more pain?

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612cd16$0$6402$9a6e19ea (AT) unlimited (DOT) newshosting.com...
There is a special tool my book calls an 'exerciser' to test the idle
stepper. The book sort of implies a high moves the pintle out and a
low in, but it doesn't say for sure.

It, the ISS has a moving part that can stand to be cleaned.

Mike

Clint wrote:
I measured before, and was getting < .5V. But whether it was exactly
.2V or not, my meter didn't give me confidence enough to say yeah or
nay.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612b0c8$0$2948$9a6e19ea (AT) unlimited (DOT) newshosting.com...
Does your meter not have a volt setting?

Mike

Clint wrote:
To go off on a (yet another) small tangent, is there a way to test
the IAS to make sure it's working correctly?

BTW, I took off the TPS, and tested the resistance as it rotated
through it's range. But without having a known good one, all I can
say is that it does go through a range of resistances smoothly.

I also learned something today, and I'm going to post it in the
interest of assisting others. Otherwise I'd just hide my red face
behind the computer screen. When putting the TPS on, the default
position seemed to have the lever arm on the wrong side of the
throttle body arm. This would cause the TPS to be rendered pretty
much useless, as far as I can see, as it won't move with the
throttle body lever. Whoops. So just watch that if you need to
replace/adjust that.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612802a$0$6626$9a6e19ea (AT) unlimited (DOT) newshosting.com...
If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter
into the back side of the plug and take a voltage reading. With
the throttle at rest, the volts should be 200 MV. At wide open,
the volts should be 4.8V max. They should smoothly increase as
the throttle opens.

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)

Clint wrote:
I've got some contact cleaner, as well as some WD40. I'll maybe
give that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make
them things out of gold. On the plus side, if I find an old
Jeep, I'm pretty sure I can haul that piece off in about 2
minutes!

I'm getting very intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for
the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of
the two.
*sigh* I thought the automatic one had an extra electrical
connector
on it? So shouldn't it be the more expensive of the two? Ah,
well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic
transmission
version in stock, but it was still $75, which seems pretty
steep for a
used part like that. I think I'll have to find a "pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the
vicinity of $75 for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray
it well
with WD40 or contact cleaner. You should be able to get some to
filter
inside. Get as close to the unit as possible and measure the
resistance
between all the pins. That !!@#$% thing is a simple rheostat so
if you
turn it as far as it goes in one direction, you should get
several ohms
(not sure of the exact value - sorry) between one of the pins
and the other
two. Leave one end of the ohm meter where it was and turn the
thing about
half way. Now you should see about half the resistance at one
of the pins.
Swap thing around to be sure you have contact between all 3 pins
at some
point. I have been able to clean the wiper arm in a couple of
them by
soaking the thing in WD40 for a days or so - the shaft is not
sealed, so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee,
and Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

#30

Left or right side? Can you give me more specific directions on what I'm
looking for (besides a dangling hose)? Should I be looking up from
underneath?

All these problems (idling) seemed to start when I replaced the rad and
water pump, so this very well could be the culprit.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote

Quote:

Now I am more thinking you are missing something... CCV unplugged or one
of the lines to the air filter box. There is one way down low in the
front by the rad that controls the heat pipe for the air filter.

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)

Clint wrote:
So I went out to a local wrecker, and they had about 6 Cherokee's, all of
about the right vintage. 3 of them still had their IAC's, but all of
them were automatic's, so I couldn't yank the TPS's. Kind of
disappointed by the lack of selection on those.

Anyway, the "new" IAC only cost $2 (the entire throttle body with add-ons
was only $20), but it had exactly the same effect as the old one. *sigh*
So I'm still looking for a TPS to plug in there.

Anyone know if the automatic tranny version of the sensor has any hope of
working? Or would I just be asking for even more pain?

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612cd16$0$6402$9a6e19ea (AT) unlimited (DOT) newshosting.com...
There is a special tool my book calls an 'exerciser' to test the idle
stepper. The book sort of implies a high moves the pintle out and a low
in, but it doesn't say for sure.

It, the ISS has a moving part that can stand to be cleaned.

Mike

Clint wrote:
I measured before, and was getting < .5V. But whether it was exactly
.2V or not, my meter didn't give me confidence enough to say yeah or
nay.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612b0c8$0$2948$9a6e19ea (AT) unlimited (DOT) newshosting.com...
Does your meter not have a volt setting?

Mike

Clint wrote:
To go off on a (yet another) small tangent, is there a way to test
the IAS to make sure it's working correctly?

BTW, I took off the TPS, and tested the resistance as it rotated
through it's range. But without having a known good one, all I can
say is that it does go through a range of resistances smoothly.

I also learned something today, and I'm going to post it in the
interest of assisting others. Otherwise I'd just hide my red face
behind the computer screen. When putting the TPS on, the default
position seemed to have the lever arm on the wrong side of the
throttle body arm. This would cause the TPS to be rendered pretty
much useless, as far as I can see, as it won't move with the throttle
body lever. Whoops. So just watch that if you need to replace/adjust
that.

Clint

"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote in message
news:4612802a$0$6626$9a6e19ea (AT) unlimited (DOT) newshosting.com...
If you have a multimeter, here are the pinouts for the TPS.

With the key in run and the engine and AC off, you put the meter
into the back side of the plug and take a voltage reading. With the
throttle at rest, the volts should be 200 MV. At wide open, the
volts should be 4.8V max. They should smoothly increase as the
throttle opens.

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)

Clint wrote:
I've got some contact cleaner, as well as some WD40. I'll maybe
give that a whirl.

As far as suppliers goes, that's the kind of price I was
hoping/expecting. But apparently up here in Canada, they make them
things out of gold. On the plus side, if I find an old Jeep, I'm
pretty sure I can haul that piece off in about 2 minutes!

I'm
getting very intimate with my throttle area...

Clint

"Will Honea" <whonea (AT) yahoo (DOT) com> wrote in message
news:46121333$0$494$815e3792 (AT) news (DOT) qwest.net...
Clint wrote:

So I stopped by the local parts place, and they wanted $280 for
the
sensor! The manual transmission one was twice as much as the
automatic one, and of course, I've got the more expensive of the
two.
*sigh* I thought the automatic one had an extra electrical
connector
on it? So shouldn't it be the more expensive of the two? Ah,
well,
logic isn't required, I guess.

I checked a "parts recycler", and they had the automatic
transmission
version in stock, but it was still $75, which seems pretty steep
for a
used part like that. I think I'll have to find a
"pick-your-part"
type place. I can yank it out in no time, at least.

I checked Advanced Auto Parts online and they get in the vicinity
of $75 for
a new one - several suppliers to chose from.

Before you go throwing money at it, remove the old one and spray
it well
with WD40 or contact cleaner. You should be able to get some to
filter
inside. Get as close to the unit as possible and measure the
resistance
between all the pins. That !!@#$% thing is a simple rheostat so
if you
turn it as far as it goes in one direction, you should get several
ohms
(not sure of the exact value - sorry) between one of the pins and
the other
two. Leave one end of the ohm meter where it was and turn the
thing about
half way. Now you should see about half the resistance at one of
the pins.
Swap thing around to be sure you have contact between all 3 pins
at some
point. I have been able to clean the wiper arm in a couple of
them by
soaking the thing in WD40 for a days or so - the shaft is not
sealed, so
the solvent will seep in - and it sure beats $75!

FYI, AA lists the same part for the 87-90 Comanche, Cherokee, and
Wagoneer
with the 4.0 engine.

--
Will Honea
whonea (AT) yahoo (DOT) com

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Still having high idle problem on 88 Jeep Comanche (4.0l)

Jeep and Willys Vehicles Discussions on Jeep and Willys vehicles. (rec.autos.makers.jeep+willys)

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 09:00 AM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 11:26 AM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 02:35 PM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 02:54 PM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 04:15 PM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 04:54 PM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 06:28 PM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 07:38 PM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 08:13 PM

Re: Still having high idle problem on 88 Jeep Comanche (4.0l) - 04-03-2007 , 08:52 PM