A Cars forum. AutoBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AutoBanter forum » Auto makers » Jeep
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

ECU for Jeep Cherokee



 
 
Thread Tools Display Modes
  #21  
Old June 16th 05, 11:22 PM
reigelser
external usenet poster
 
Posts: n/a
Default

Haven't gotten the OBD reader yet, therefore no progress in this matter.
Drove the car today. Not too bad, slight bucking. Hope to get to it Friday.
Don't forget to check back please.

"DougW" > wrote in message
news:duqre.15928$mC.2210@okepread07...
> reigelser did pass the time by typing:
>> I need the ECU eventually because of a persistent TPS error. My mechanic
>> troubleshooted it and thinks its probably the ECU. But he thinks there
>> has
>> to be some reprogramming to be done, because I tried one from the junk
>> yard
>> before he looked into it and nothing changed (same TPS error, same
>> mileage).
>> It's a 97 inline 6 Cherokee. It works, but it doesn't start at first try
>> and
>> it is not very smooth if you want to accelerate from 65 to 75 without a
>> kickdown.

>
> Clean the connectors at both the TPS and the ECU.
> And while you have the plugs off, ohm out the sensor
> lines as the TPS shares a common ground link with
> other sensors and that link can go wonky.
>
> All I have is the 93 schematic so you need the color codes for
> your year.
>
> --
> DougW
>



Ads
  #22  
Old June 17th 05, 10:26 PM
reigelser
external usenet poster
 
Posts: n/a
Default

Hi,
I did the proposed alignment procedure and I cleaned all contacts with a
special contact cleaner. Nothing changed. I can not reset the error. The
voltages are 5.1V constant supply ground to pin 1. Then the voltage between
Pin1 and 2 is between 1.1V (fully closed) and 4.2V fully open. Between the
pin 2 and ground the voltage is 3.9V fully closed and 1.1V fully open. I
measured the resistance of the common ground of the Map, the TPS and the
Crankshaft sensor and its good.
I guess I am running out of options, since I also cleaned the throttle body
with carburator cleaner prior to putting it into the car.
Does anybody have another idea? The thought to get a new ECU for 450$
without knowing if it fixes it is not funny.
Thanks again
Jo
"Stephen Cowell" > wrote in message
. ..

"DougW" > wrote in message
news:niMre.15993$mC.9041@okepread07...
> reigelser did pass the time by typing:
> > I just tried the proposed starting procedure. KeyOnEngineoff for 10sec
> > and
> > then crank but no vroom. I needed a second try. When I turn the key I
> > hear
> > the Fuel pump for approx 1sec (I believe its the fuel pump).

>
> Your correct, the pump runs (primes) the system for about 1 sec.
>
> > With the engine
> > cold there is a little delay in the throttle response. Between Pushing
> > the
> > throttle a bit and the revs coming up is a ~0.5sec delay. When I rev the
> > engine at 2000 and go of the Throttle it goes all the way down to
> > ~300rpm
> > before it comes up to 800 again.0

>
> That's normal. Your letting off the throttle is telling the engine to
> go into braking mode.


I disagree... 300rpm is not normal... I feel that the idle air
solenoid is closing down when he opens the throttle, then
motoring back up after the throttle hits the closed stop.
This certainly points to a TPS problem.... let's see what
happens after he performs the TPS alignment procedure
you gave.
__
Steve
..



  #23  
Old June 18th 05, 12:18 AM
DougW
external usenet poster
 
Posts: n/a
Default

reigelser did pass the time by typing:
> Hi,
> I did the proposed alignment procedure and I cleaned all contacts with a
> special contact cleaner. Nothing changed. I can not reset the error. The
> voltages are 5.1V constant supply ground to pin 1. Then the voltage between
> Pin1 and 2 is between 1.1V (fully closed) and 4.2V fully open. Between the
> pin 2 and ground the voltage is 3.9V fully closed and 1.1V fully open. I
> measured the resistance of the common ground of the Map, the TPS and the
> Crankshaft sensor and its good.
> I guess I am running out of options, since I also cleaned the throttle body
> with carburator cleaner prior to putting it into the car.
> Does anybody have another idea? The thought to get a new ECU for 450$
> without knowing if it fixes it is not funny.
> Thanks again


As much as I don't like throwing parts at a problem you might
want to try the MAP sensor before the ECU. When it comes to paying
out $450 it's also a good idea just to take it into a dealership
and have them do a full diagnostic on the engine.

I've gone through two MAP sensors and the symptoms are usually
some stubling along with a gutless acceleration except when the
gas is floored or when the engine is running in warmup-mode.

Just for grins, check the O2 sensor lead as it goes up the front
of the block and make sure it's not melted or abraided. This
can cause headaches to the ECU.

--
DougW


  #24  
Old June 18th 05, 01:20 AM
tim bur
external usenet poster
 
Posts: n/a
Default

i would replace the tps the pcm is working correctly as far as voltage

DougW wrote:

> reigelser did pass the time by typing:
> > Hi,
> > I did the proposed alignment procedure and I cleaned all contacts with a
> > special contact cleaner. Nothing changed. I can not reset the error. The
> > voltages are 5.1V constant supply ground to pin 1. Then the voltage between
> > Pin1 and 2 is between 1.1V (fully closed) and 4.2V fully open. Between the
> > pin 2 and ground the voltage is 3.9V fully closed and 1.1V fully open. I
> > measured the resistance of the common ground of the Map, the TPS and the
> > Crankshaft sensor and its good.
> > I guess I am running out of options, since I also cleaned the throttle body
> > with carburator cleaner prior to putting it into the car.
> > Does anybody have another idea? The thought to get a new ECU for 450$
> > without knowing if it fixes it is not funny.
> > Thanks again

>
> As much as I don't like throwing parts at a problem you might
> want to try the MAP sensor before the ECU. When it comes to paying
> out $450 it's also a good idea just to take it into a dealership
> and have them do a full diagnostic on the engine.
>
> I've gone through two MAP sensors and the symptoms are usually
> some stubling along with a gutless acceleration except when the
> gas is floored or when the engine is running in warmup-mode.
>
> Just for grins, check the O2 sensor lead as it goes up the front
> of the block and make sure it's not melted or abraided. This
> can cause headaches to the ECU.
>
> --
> DougW


  #25  
Old June 18th 05, 01:22 AM
tim bur
external usenet poster
 
Posts: n/a
Default

can u email me with the whole story from start to now,and include the fault code

DougW wrote:

> reigelser did pass the time by typing:
> > Hi,
> > I did the proposed alignment procedure and I cleaned all contacts with a
> > special contact cleaner. Nothing changed. I can not reset the error. The
> > voltages are 5.1V constant supply ground to pin 1. Then the voltage between
> > Pin1 and 2 is between 1.1V (fully closed) and 4.2V fully open. Between the
> > pin 2 and ground the voltage is 3.9V fully closed and 1.1V fully open. I
> > measured the resistance of the common ground of the Map, the TPS and the
> > Crankshaft sensor and its good.
> > I guess I am running out of options, since I also cleaned the throttle body
> > with carburator cleaner prior to putting it into the car.
> > Does anybody have another idea? The thought to get a new ECU for 450$
> > without knowing if it fixes it is not funny.
> > Thanks again

>
> As much as I don't like throwing parts at a problem you might
> want to try the MAP sensor before the ECU. When it comes to paying
> out $450 it's also a good idea just to take it into a dealership
> and have them do a full diagnostic on the engine.
>
> I've gone through two MAP sensors and the symptoms are usually
> some stubling along with a gutless acceleration except when the
> gas is floored or when the engine is running in warmup-mode.
>
> Just for grins, check the O2 sensor lead as it goes up the front
> of the block and make sure it's not melted or abraided. This
> can cause headaches to the ECU.
>
> --
> DougW


  #26  
Old June 18th 05, 04:43 PM
reigelser
external usenet poster
 
Posts: n/a
Default

Here the full story:

The enginelight came on about 6 weeks ago. Evaluation with the OBD reader
showed a P0123. So I replaced the TPS. While doing that I stripped a thread
on the throttle body. The tps was fixed with one screw, the error was still
there. I found a god throttle body on a junk yard and replaced the existing
one. The one from the junk yard came with all sensors (MAP, TPS and Idle
Motor) and the problem was exactly the same. All Voltages measured right,
error code P0123. So I got a new ECU from the junk yard and put it in. Same
exact error message, not resetable P0123. I put the old ECU back in and gave
the ECU back to the junk yard. Then I gave the car to the mechanic who did
some troubleshooting and told me its most likely the ECU. When I told him I
replaced it allready, he mentioned that on some vehicles (he had problems
with chevy ecus) a reprogramming is required that just the official dealers
can do. A new ecu for the jeep is 480$ approx. As you could see in the
newsgroup I followed the advice and checked all electrical connections,
measured the common ground and the grounding of the engine block, cleaned
the contacts and did reteaching of the ecu.

The driving is not bad with the car. It starts at 2nd try always, in the
beginning with the old throttle body it would stall when it was cold, but
now it doesn't anymore. When the engine is cold the first couple of hundred
yards it runs a bit rough (throttle response is slow)but then it just jumps
a little bit for example on the high way when accelerating from 65 to 75
with little gas. There seems to be one position of the gas in that regime
where it almost goes into a resonant oscillation (difficult to explain, it
feels like going on and off the gas in 0.5 sec distance even though the
throttle isn't moved at all).

If you have any additional ideas and good advice that would be highly
appreciated. I want to make sure to do everythiong possible before I put the
car to a Jeep dealer.

Thanks

Joachim

"tim bur" > wrote in message
...
> can u email me with the whole story from start to now,and include the
> fault code
>
> DougW wrote:
>
>> reigelser did pass the time by typing:
>> > Hi,
>> > I did the proposed alignment procedure and I cleaned all contacts with
>> > a
>> > special contact cleaner. Nothing changed. I can not reset the error.
>> > The
>> > voltages are 5.1V constant supply ground to pin 1. Then the voltage
>> > between
>> > Pin1 and 2 is between 1.1V (fully closed) and 4.2V fully open. Between
>> > the
>> > pin 2 and ground the voltage is 3.9V fully closed and 1.1V fully open.
>> > I
>> > measured the resistance of the common ground of the Map, the TPS and
>> > the
>> > Crankshaft sensor and its good.
>> > I guess I am running out of options, since I also cleaned the throttle
>> > body
>> > with carburator cleaner prior to putting it into the car.
>> > Does anybody have another idea? The thought to get a new ECU for 450$
>> > without knowing if it fixes it is not funny.
>> > Thanks again

>>
>> As much as I don't like throwing parts at a problem you might
>> want to try the MAP sensor before the ECU. When it comes to paying
>> out $450 it's also a good idea just to take it into a dealership
>> and have them do a full diagnostic on the engine.
>>
>> I've gone through two MAP sensors and the symptoms are usually
>> some stubling along with a gutless acceleration except when the
>> gas is floored or when the engine is running in warmup-mode.
>>
>> Just for grins, check the O2 sensor lead as it goes up the front
>> of the block and make sure it's not melted or abraided. This
>> can cause headaches to the ECU.
>>
>> --
>> DougW

>



  #27  
Old June 25th 05, 02:29 AM
reigelser
external usenet poster
 
Posts: n/a
Default

Hi, the problem is solved. 2 days after I sprayed everything with contact
cleaner, the error went away by itself. That was 4 days ago. Self healing
Jeep. Let's see if it stays like that.

Thanks for all the help and advice.

Jo
"reigelser" > wrote in message
...
> Hi,
> does anybody know, if there is some programming or calibration to be done
> if the engine control unit is replaced? Or do I just plug it in and thats
> it?
> Thanks for the advice.
>
> Jo
>
>



 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Jeep Grand Cherokee 5.7 Hemi in UK Dori A Schmetterling Chrysler 4 June 2nd 05 10:22 PM
94 Cherokee Manual required 94JeepMan Jeep 12 April 29th 05 06:21 PM
1994 Jeep Cherokee 4WD Automatic Transmission questions brookman1973 Jeep 11 February 13th 05 07:42 PM
4WD (Cherokee?) recommendations please coyotefred 4x4 6 June 20th 04 04:13 AM


All times are GMT +1. The time now is 11:29 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AutoBanter.
The comments are property of their posters.