1990 AW4 not liking 1-2 shift anymore
04-21-2015, 10:00 AM
#31
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,875
Received 1,526 Likes
on
1,238 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
I have not said anything about this because I thought it didn't matter.
A few years back my XJ was stolen. During the time it was gone, #2 injector leaked and caught fire. The result burned up my engine harness, among other things. The only harness I could find was a 1989 with the dredded C101. I went through the connections again to make sure they are good. I know the TPS trans side wires pass through there. My grounds are good, and voltmeter verified.
Just wanted to add that into the messpile.
A few years back my XJ was stolen. During the time it was gone, #2 injector leaked and caught fire. The result burned up my engine harness, among other things. The only harness I could find was a 1989 with the dredded C101. I went through the connections again to make sure they are good. I know the TPS trans side wires pass through there. My grounds are good, and voltmeter verified.
Just wanted to add that into the messpile.
04-21-2015, 10:50 AM
#32
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
I was hoping it would not come to that. I have been looking for a new harness for a while just to get that one out of there. I am going to do some testing at the TCU, and report back. I AM supposed to be working, but you know how it is. At least i am AT work....
04-21-2015, 11:02 AM
#33
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
Too bad my 100th post is not a "yay" type post.
Checked TPS values from the TCU and they are good. The output is 83% of reference.
Checked TPS values from the TCU and they are good. The output is 83% of reference.
04-21-2015, 12:47 PM
#34
CF Veteran
Join Date: Aug 2011
Location: Nor-Cal Coast
Posts: 10,489
Likes: 0
Received 17 Likes
on
17 Posts
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Well, happy 100'th anyway! Like I mentioned in post #17, it seems issues do come up with our TCU's.
Right now I'm having a similar problem with my White 90. (Intermittent) High shift points. Sometimes letting off will make it up shift, sometimes not. Since I have an identical TCU in my Brown 90 I intend to swap them and see. Maybe I can get to that today. Also I'm unclear if there could be an issue with the speed sensor.
Right now I'm having a similar problem with my White 90. (Intermittent) High shift points. Sometimes letting off will make it up shift, sometimes not. Since I have an identical TCU in my Brown 90 I intend to swap them and see. Maybe I can get to that today. Also I'm unclear if there could be an issue with the speed sensor.
Last edited by DFlintstone; 04-21-2015 at 04:24 PM.
04-21-2015, 01:52 PM
#35
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
Right on. I guess i will know for sure when I wire in the shift switches again. I have to go home and grab them first. Its my wife's birthday though, so I doubt I will get anything done once I get home.
04-21-2015, 03:23 PM
#36
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
yeah, the switches do nothing for the situation. Voltmeter tells me wires and connections are good. I think I'm done
04-21-2015, 04:38 PM
#37
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
Not the NSS, not the wires between the AW4 and the connector at the firewall. not the wires between the TCU and the connector at the firewall. I am at a loss.
04-21-2015, 05:41 PM
#38
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,875
Received 1,526 Likes
on
1,238 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
What about the C101 you were referring to earlier?
04-21-2015, 07:38 PM
#39
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
I pulled it apart a few days back and cleaned it. Your reference to #27 made me pick up more solder and heat shrink on my way home.
My wife would shoot me if I undertook that tonight.
Funny thing is I didn't have to browse my .pdf again to know what the "dredded 27" was.
My wife would shoot me if I undertook that tonight.
Funny thing is I didn't have to browse my .pdf again to know what the "dredded 27" was.
Last edited by Gearhead-XJ90; 04-21-2015 at 08:04 PM. Reason: Additional line at bottom
04-21-2015, 09:16 PM
#40
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,875
Received 1,526 Likes
on
1,238 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
I pulled it apart a few days back and cleaned it. Your reference to #27 made me pick up more solder and heat shrink on my way home.
My wife would shoot me if I undertook that tonight.
Funny thing is I didn't have to browse my .pdf again to know what the "dredded 27" was.
My wife would shoot me if I undertook that tonight.
Funny thing is I didn't have to browse my .pdf again to know what the "dredded 27" was.
04-22-2015, 11:01 AM
#41
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
Well I had to go pick up some supplies, and for the hell of it decided to un-jumper the pow/comf switch. Immediately my shift point from 1-2 dropped to 2200rpm. That is where it was before, but i have always had the switch "on" until i jumped the switch like I was asked to in a previous post.
Just thought I would share. Will still be doing the C101 delete hopefully tonight.
Just thought I would share. Will still be doing the C101 delete hopefully tonight.
04-22-2015, 04:38 PM
#42
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,875
Received 1,526 Likes
on
1,238 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Well I had to go pick up some supplies, and for the hell of it decided to un-jumper the pow/comf switch. Immediately my shift point from 1-2 dropped to 2200rpm. That is where it was before, but i have always had the switch "on" until i jumped the switch like I was asked to in a previous post.
Just thought I would share. Will still be doing the C101 delete hopefully tonight.
Just thought I would share. Will still be doing the C101 delete hopefully tonight.
04-22-2015, 04:54 PM
#43
Member
Thread Starter
Join Date: Jul 2011
Location: Sevier County, TN
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
Yeah, I figured as much. At least I can drive it without over-revving first until I find the underlying problem.
On another note. When I stated wiring the switches to bypass the TCU yielded no luck, I might have been wrong. I was using a new switch from the parts pile, when I went to use it today to test something else on a different beast I learned the switch is bad. I am going to pick up another switch tonight on the way home.
I'm trying to narrow it down the either the TCU or Tip #27. 27 will be done either way, but I want to rule out the TCU as well.
On another note. When I stated wiring the switches to bypass the TCU yielded no luck, I might have been wrong. I was using a new switch from the parts pile, when I went to use it today to test something else on a different beast I learned the switch is bad. I am going to pick up another switch tonight on the way home.
I'm trying to narrow it down the either the TCU or Tip #27. 27 will be done either way, but I want to rule out the TCU as well.
04-22-2015, 04:59 PM
#44
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,875
Received 1,526 Likes
on
1,238 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
C101 delete.
P/C switch bypass
Possible TCU, but, if you read Tip 1 closely, you can see that the tCU and it's shift logic circuit ground at the engine dipstick tube stud.
P/C switch bypass
Possible TCU, but, if you read Tip 1 closely, you can see that the tCU and it's shift logic circuit ground at the engine dipstick tube stud.
04-22-2015, 05:17 PM
#45
CF Veteran
Join Date: Aug 2011
Location: Nor-Cal Coast
Posts: 10,489
Likes: 0
Received 17 Likes
on
17 Posts
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
This morning white wasn't up shifting. I reached down to fiddle with the comfort switch, but hit the (not functioning), rear wiper switch instead. Right then it shifted. Probably a coincidence, or some idiot plugged wires in the wrong prongs.