Jeep Wrangler High Idle Problem

On Aug 14, 6:58 am, Mike Romain > wrote:
> The TPS is a resistance based switch just like a volume control. You
> can even test it with a multimeter set on ohms or live with the meter
> set on volts.
>
> If it has a bad connection, this connection has a resistance factor that
> isn't supposed to be there or an arcing issue which causes surges.
>
> When ours got a dirty connection, it would usually stall at the first
> stop and get stuck on a 1500 to 2000 rpm fast idle. We were told back
> in the 90's that we needed a new TPS in our Cherokee, We just retired
> the Cherokee recently with that same 'dead' TPS in it....
>
> All the computer sensors are very low power items that are very touchy
> about their connections.
>
> A spray can of electroniccontact cleanerwill be a very good friend to
> you as the Jeep gets older. It will sure save you money, because
> changing out parts only fixes 'half' the connection...
>
> Mike
>
>
>
> 97tjMike wrote:
> > How would the TPS affect idle speed? From my understanding, it is just
> > a sending unit, meaning it can only give information to the PCM but
> > cannot receive and therefore manipulate any settings.
>
> > On Aug 13, 1:47 pm, Mike Romain > wrote:
> >> Will Honea wrote:
> >>> 97tjMike wrote:
> >>>> Hello Everyone:
> >>>> I have a 97 TJ and 95% of the time it idles perfectly. However, about
> >>>> 5% of the time, usually when the vehicle has been run for more than 20
> >>>> minutes or so, the idle in neutral or park will shoot up to between
> >>>> 1200 and 1500 RPM. The only way to get it to stop is to put the
> >>>> vehicle into gear or to restart the car. If I restart it, it will not
> >>>> happen for a while, but it eventually comes back. The TPS was recently
> >>>> replaced, and I just replaced the idle air control valve, thinking
> >>>> this may have been the problem, but it still has the same effect. I'm
> >>>> thinking now that it may be the coolant temperature sensor (something
> >>>> wacky when the engine is hotter making the vehicle run at higher
> >>>> speeds??). Any suggestions? I'm hoping its not my computer...
> >>> Clean the TPS connector. Go to an electronics parts store and buy some
> >>>contact cleaneror WD40 works. Disconnect the TPS, clean, connect and
> >>> disconnect several times, blow dry, then use some dielectric grease on the
> >>> the connector seal ring to keep moisture out.
> >> Yup, replacing parts only cleans 'half' the connection.
>
> >> Mike
> >> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> >> Canadian Off Road Trips Photos: Non members can still view!
> >> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> >> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -

The best contact cleaner stuff is DeoxIT, www.deoxit.com
You can get it at RadioShack, Fry's and other electronic stores:
http://store.caig.com/s.nl/sc.15/category.295/.f
Work's everytime for me.
Mike

The Wrangler was in high idle today so I decided to investigate. I
disconnected the TPS Sensor and the idle went back down to its normal
RPMs. I then reconnected it and the RPMs went back up. Tried cleaning
contacts, not help there. Perhaps the TPS is defective? It's still
under warranty so I can just bring it back.

Mike

On Aug 14, 9:58 am, Mike Romain > wrote:
> The TPS is a resistance based switch just like a volume control. You
> can even test it with a multimeter set on ohms or live with the meter
> set on volts.
>
> If it has a bad connection, this connection has a resistance factor that
> isn't supposed to be there or an arcing issue which causes surges.
>
> When ours got a dirty connection, it would usually stall at the first
> stop and get stuck on a 1500 to 2000 rpm fast idle. We were told back
> in the 90's that we needed a new TPS in our Cherokee, We just retired
> the Cherokee recently with that same 'dead' TPS in it....
>
> All the computer sensors are very low power items that are very touchy
> about their connections.
>
> A spray can of electronic contact cleaner will be a very good friend to
> you as the Jeep gets older. It will sure save you money, because
> changing out parts only fixes 'half' the connection...
>
> Mike
>
> 97tjMike wrote:
> > How would the TPS affect idle speed? From my understanding, it is just
> > a sending unit, meaning it can only give information to the PCM but
> > cannot receive and therefore manipulate any settings.
>
> > On Aug 13, 1:47 pm, Mike Romain > wrote:
> >> Will Honea wrote:
> >>> 97tjMike wrote:
> >>>> Hello Everyone:
> >>>> I have a 97 TJ and 95% of the time it idles perfectly. However, about
> >>>> 5% of the time, usually when the vehicle has been run for more than 20
> >>>> minutes or so, the idle in neutral or park will shoot up to between
> >>>> 1200 and 1500 RPM. The only way to get it to stop is to put the
> >>>> vehicle into gear or to restart the car. If I restart it, it will not
> >>>> happen for a while, but it eventually comes back. The TPS was recently
> >>>> replaced, and I just replaced the idle air control valve, thinking
> >>>> this may have been the problem, but it still has the same effect. I'm
> >>>> thinking now that it may be the coolant temperature sensor (something
> >>>> wacky when the engine is hotter making the vehicle run at higher
> >>>> speeds??). Any suggestions? I'm hoping its not my computer...
> >>> Clean the TPS connector. Go to an electronics parts store and buy some
> >>> contact cleaner or WD40 works. Disconnect the TPS, clean, connect and
> >>> disconnect several times, blow dry, then use some dielectric grease on the
> >>> the connector seal ring to keep moisture out.
> >> Yup, replacing parts only cleans 'half' the connection.
>
> >> Mike
> >> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> >> Canadian Off Road Trips Photos: Non members can still view!
> >> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> >> (More Off Road album links at bottom of the view page)

You can do a voltage test on it.

If you have the AC off and the key just in 'run' with the engine off and
back probe the TPS plug with multimeter probes set to volts, it should
be at .02 volts at idle and 4.8 volts at wide open.

Mike

97tjMike wrote:
> The Wrangler was in high idle today so I decided to investigate. I
> disconnected the TPS Sensor and the idle went back down to its normal
> RPMs. I then reconnected it and the RPMs went back up. Tried cleaning
> contacts, not help there. Perhaps the TPS is defective? It's still
> under warranty so I can just bring it back.
>
> Mike
>
> On Aug 14, 9:58 am, Mike Romain > wrote:
>> The TPS is a resistance based switch just like a volume control. You
>> can even test it with a multimeter set on ohms or live with the meter
>> set on volts.
>>
>> If it has a bad connection, this connection has a resistance factor that
>> isn't supposed to be there or an arcing issue which causes surges.
>>
>> When ours got a dirty connection, it would usually stall at the first
>> stop and get stuck on a 1500 to 2000 rpm fast idle. We were told back
>> in the 90's that we needed a new TPS in our Cherokee, We just retired
>> the Cherokee recently with that same 'dead' TPS in it....
>>
>> All the computer sensors are very low power items that are very touchy
>> about their connections.
>>
>> A spray can of electronic contact cleaner will be a very good friend to
>> you as the Jeep gets older. It will sure save you money, because
>> changing out parts only fixes 'half' the connection...
>>
>> Mike
>>
>> 97tjMike wrote:
>>> How would the TPS affect idle speed? From my understanding, it is just
>>> a sending unit, meaning it can only give information to the PCM but
>>> cannot receive and therefore manipulate any settings.
>>> On Aug 13, 1:47 pm, Mike Romain > wrote:
>>>> Will Honea wrote:
>>>>> 97tjMike wrote:
>>>>>> Hello Everyone:
>>>>>> I have a 97 TJ and 95% of the time it idles perfectly. However, about
>>>>>> 5% of the time, usually when the vehicle has been run for more than 20
>>>>>> minutes or so, the idle in neutral or park will shoot up to between
>>>>>> 1200 and 1500 RPM. The only way to get it to stop is to put the
>>>>>> vehicle into gear or to restart the car. If I restart it, it will not
>>>>>> happen for a while, but it eventually comes back. The TPS was recently
>>>>>> replaced, and I just replaced the idle air control valve, thinking
>>>>>> this may have been the problem, but it still has the same effect. I'm
>>>>>> thinking now that it may be the coolant temperature sensor (something
>>>>>> wacky when the engine is hotter making the vehicle run at higher
>>>>>> speeds??). Any suggestions? I'm hoping its not my computer...
>>>>> Clean the TPS connector. Go to an electronics parts store and buy some
>>>>> contact cleaner or WD40 works. Disconnect the TPS, clean, connect and
>>>>> disconnect several times, blow dry, then use some dielectric grease on the
>>>>> the connector seal ring to keep moisture out.
>>>> Yup, replacing parts only cleans 'half' the connection.
>>>> Mike
>>>> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>>> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
>>>> Canadian Off Road Trips Photos: Non members can still view!
>>>> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
>>>> (More Off Road album links at bottom of the view page)
>
>

AC? I have a JEEP remember?!?!?!? jk thanks for the specs I'll test it
tomorrow. One question...there are 3 terminals, which ones do I hook
up the multimeter to?

On Aug 15, 5:50 pm, Mike Romain > wrote:
> You can do a voltage test on it.
>
> If you have the AC off and the key just in 'run' with the engine off and
> back probe the TPS plug with multimeter probes set to volts, it should
> be at .02 volts at idle and 4.8 volts at wide open.
>
> Mike
>
> 97tjMike wrote:
> > The Wrangler was in high idle today so I decided to investigate. I
> > disconnected the TPS Sensor and the idle went back down to its normal
> > RPMs. I then reconnected it and the RPMs went back up. Tried cleaning
> > contacts, not help there. Perhaps the TPS is defective? It's still
> > under warranty so I can just bring it back.
>
> > Mike
>
> > On Aug 14, 9:58 am, Mike Romain > wrote:
> >> The TPS is a resistance based switch just like a volume control. You
> >> can even test it with a multimeter set on ohms or live with the meter
> >> set on volts.
>
> >> If it has a bad connection, this connection has a resistance factor that
> >> isn't supposed to be there or an arcing issue which causes surges.
>
> >> When ours got a dirty connection, it would usually stall at the first
> >> stop and get stuck on a 1500 to 2000 rpm fast idle. We were told back
> >> in the 90's that we needed a new TPS in our Cherokee, We just retired
> >> the Cherokee recently with that same 'dead' TPS in it....
>
> >> All the computer sensors are very low power items that are very touchy
> >> about their connections.
>
> >> A spray can of electronic contact cleaner will be a very good friend to
> >> you as the Jeep gets older. It will sure save you money, because
> >> changing out parts only fixes 'half' the connection...
>
> >> Mike
>
> >> 97tjMike wrote:
> >>> How would the TPS affect idle speed? From my understanding, it is just
> >>> a sending unit, meaning it can only give information to the PCM but
> >>> cannot receive and therefore manipulate any settings.
> >>> On Aug 13, 1:47 pm, Mike Romain > wrote:
> >>>> Will Honea wrote:
> >>>>> 97tjMike wrote:
> >>>>>> Hello Everyone:
> >>>>>> I have a 97 TJ and 95% of the time it idles perfectly. However, about
> >>>>>> 5% of the time, usually when the vehicle has been run for more than 20
> >>>>>> minutes or so, the idle in neutral or park will shoot up to between
> >>>>>> 1200 and 1500 RPM. The only way to get it to stop is to put the
> >>>>>> vehicle into gear or to restart the car. If I restart it, it will not
> >>>>>> happen for a while, but it eventually comes back. The TPS was recently
> >>>>>> replaced, and I just replaced the idle air control valve, thinking
> >>>>>> this may have been the problem, but it still has the same effect. I'm
> >>>>>> thinking now that it may be the coolant temperature sensor (something
> >>>>>> wacky when the engine is hotter making the vehicle run at higher
> >>>>>> speeds??). Any suggestions? I'm hoping its not my computer...
> >>>>> Clean the TPS connector. Go to an electronics parts store and buy some
> >>>>> contact cleaner or WD40 works. Disconnect the TPS, clean, connect and
> >>>>> disconnect several times, blow dry, then use some dielectric grease on the
> >>>>> the connector seal ring to keep moisture out.
> >>>> Yup, replacing parts only cleans 'half' the connection.
> >>>> Mike
> >>>> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >>>> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> >>>> Canadian Off Road Trips Photos: Non members can still view!
> >>>> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> >>>> (More Off Road album links at bottom of the view page)

On Wed, 15 Aug 2007 20:12:26 -0700, 97tjMike >
wrote:

>AC? I have a JEEP remember?!?!?!? jk thanks for the specs I'll test it
>tomorrow. One question...there are 3 terminals, which ones do I hook
>up the multimeter to?
>

One of them should be a ground, one of them's a 5v reference voltage
that won't change and the other one should vary between the values
Mike gave you as you move the throttle.
--
Old Crow "Yol Bolsun!"
'82 FLTC-P "Miss Pearl"
'95 YJ Rio Grande
BS#133, SENS, TOMKAT, MAMBM


--
Posted via a free Usenet account from http://www.teranews.com

ok tested.
closed: .938v
open: 3.9v

defective TPS?


On Aug 15, 5:50 pm, Mike Romain > wrote:
> You can do a voltage test on it.
>
> If you have the AC off and the key just in 'run' with the engine off and
> back probe the TPS plug with multimeter probes set to volts, it should
> be at .02 volts at idle and 4.8 volts at wide open.
>
> Mike
>
> 97tjMike wrote:
> > The Wrangler was in high idle today so I decided to investigate. I
> > disconnected the TPS Sensor and the idle went back down to its normal
> > RPMs. I then reconnected it and the RPMs went back up. Tried cleaning
> > contacts, not help there. Perhaps the TPS is defective? It's still
> > under warranty so I can just bring it back.
>
> > Mike
>
> > On Aug 14, 9:58 am, Mike Romain > wrote:
> >> The TPS is a resistance based switch just like a volume control. You
> >> can even test it with a multimeter set on ohms or live with the meter
> >> set on volts.
>
> >> If it has a bad connection, this connection has a resistance factor that
> >> isn't supposed to be there or an arcing issue which causes surges.
>
> >> When ours got a dirty connection, it would usually stall at the first
> >> stop and get stuck on a 1500 to 2000 rpm fast idle. We were told back
> >> in the 90's that we needed a new TPS in our Cherokee, We just retired
> >> the Cherokee recently with that same 'dead' TPS in it....
>
> >> All the computer sensors are very low power items that are very touchy
> >> about their connections.
>
> >> A spray can of electronic contact cleaner will be a very good friend to
> >> you as the Jeep gets older. It will sure save you money, because
> >> changing out parts only fixes 'half' the connection...
>
> >> Mike
>
> >> 97tjMike wrote:
> >>> How would the TPS affect idle speed? From my understanding, it is just
> >>> a sending unit, meaning it can only give information to the PCM but
> >>> cannot receive and therefore manipulate any settings.
> >>> On Aug 13, 1:47 pm, Mike Romain > wrote:
> >>>> Will Honea wrote:
> >>>>> 97tjMike wrote:
> >>>>>> Hello Everyone:
> >>>>>> I have a 97 TJ and 95% of the time it idles perfectly. However, about
> >>>>>> 5% of the time, usually when the vehicle has been run for more than 20
> >>>>>> minutes or so, the idle in neutral or park will shoot up to between
> >>>>>> 1200 and 1500 RPM. The only way to get it to stop is to put the
> >>>>>> vehicle into gear or to restart the car. If I restart it, it will not
> >>>>>> happen for a while, but it eventually comes back. The TPS was recently
> >>>>>> replaced, and I just replaced the idle air control valve, thinking
> >>>>>> this may have been the problem, but it still has the same effect. I'm
> >>>>>> thinking now that it may be the coolant temperature sensor (something
> >>>>>> wacky when the engine is hotter making the vehicle run at higher
> >>>>>> speeds??). Any suggestions? I'm hoping its not my computer...
> >>>>> Clean the TPS connector. Go to an electronics parts store and buy some
> >>>>> contact cleaner or WD40 works. Disconnect the TPS, clean, connect and
> >>>>> disconnect several times, blow dry, then use some dielectric grease on the
> >>>>> the connector seal ring to keep moisture out.
> >>>> Yup, replacing parts only cleans 'half' the connection.
> >>>> Mike
> >>>> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >>>> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> >>>> Canadian Off Road Trips Photos: Non members can still view!
> >>>> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> >>>> (More Off Road album links at bottom of the view page)

Sure sounds like it. The idle reading it high.

Mike

97tjMike wrote:
> ok tested.
> closed: .938v
> open: 3.9v
>
> defective TPS?
>
>
> On Aug 15, 5:50 pm, Mike Romain > wrote:
>> You can do a voltage test on it.
>>
>> If you have the AC off and the key just in 'run' with the engine off and
>> back probe the TPS plug with multimeter probes set to volts, it should
>> be at .02 volts at idle and 4.8 volts at wide open.
>>
>> Mike
>>
>> 97tjMike wrote:
>>> The Wrangler was in high idle today so I decided to investigate. I
>>> disconnected the TPS Sensor and the idle went back down to its normal
>>> RPMs. I then reconnected it and the RPMs went back up. Tried cleaning
>>> contacts, not help there. Perhaps the TPS is defective? It's still
>>> under warranty so I can just bring it back.
>>> Mike
>>> On Aug 14, 9:58 am, Mike Romain > wrote:
>>>> The TPS is a resistance based switch just like a volume control. You
>>>> can even test it with a multimeter set on ohms or live with the meter
>>>> set on volts.
>>>> If it has a bad connection, this connection has a resistance factor that
>>>> isn't supposed to be there or an arcing issue which causes surges.
>>>> When ours got a dirty connection, it would usually stall at the first
>>>> stop and get stuck on a 1500 to 2000 rpm fast idle. We were told back
>>>> in the 90's that we needed a new TPS in our Cherokee, We just retired
>>>> the Cherokee recently with that same 'dead' TPS in it....
>>>> All the computer sensors are very low power items that are very touchy
>>>> about their connections.
>>>> A spray can of electronic contact cleaner will be a very good friend to
>>>> you as the Jeep gets older. It will sure save you money, because
>>>> changing out parts only fixes 'half' the connection...
>>>> Mike
>>>> 97tjMike wrote:
>>>>> How would the TPS affect idle speed? From my understanding, it is just
>>>>> a sending unit, meaning it can only give information to the PCM but
>>>>> cannot receive and therefore manipulate any settings.
>>>>> On Aug 13, 1:47 pm, Mike Romain > wrote:
>>>>>> Will Honea wrote:
>>>>>>> 97tjMike wrote:
>>>>>>>> Hello Everyone:
>>>>>>>> I have a 97 TJ and 95% of the time it idles perfectly. However, about
>>>>>>>> 5% of the time, usually when the vehicle has been run for more than 20
>>>>>>>> minutes or so, the idle in neutral or park will shoot up to between
>>>>>>>> 1200 and 1500 RPM. The only way to get it to stop is to put the
>>>>>>>> vehicle into gear or to restart the car. If I restart it, it will not
>>>>>>>> happen for a while, but it eventually comes back. The TPS was recently
>>>>>>>> replaced, and I just replaced the idle air control valve, thinking
>>>>>>>> this may have been the problem, but it still has the same effect. I'm
>>>>>>>> thinking now that it may be the coolant temperature sensor (something
>>>>>>>> wacky when the engine is hotter making the vehicle run at higher
>>>>>>>> speeds??). Any suggestions? I'm hoping its not my computer...
>>>>>>> Clean the TPS connector. Go to an electronics parts store and buy some
>>>>>>> contact cleaner or WD40 works. Disconnect the TPS, clean, connect and
>>>>>>> disconnect several times, blow dry, then use some dielectric grease on the
>>>>>>> the connector seal ring to keep moisture out.
>>>>>> Yup, replacing parts only cleans 'half' the connection.
>>>>>> Mike
>>>>>> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>>>>> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
>>>>>> Canadian Off Road Trips Photos: Non members can still view!
>>>>>> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
>>>>>> (More Off Road album links at bottom of the view page)
>
>

Mike Romain wrote:
> Sure sounds like it. The idle reading it high.
>

Throttle closed > 200 milliVolts
Throttle wide open < 4.8 Volts
Anything in that range will adjust. The way you

3.9 is low as well.

Measure the outer two pins to make sure your getting
close to 5V.

Before getting a new one, run the old one back and
forth a few dozen times with the engine off, then
measure again. Also make sure the connector is clean
and free of crudbunnies.


> 97tjMike wrote:
>> ok tested.
>> closed: .938v
>> open: 3.9v
>>
>> defective TPS?