P0122 & P0123
#1
CF Veteran
Thread Starter
Join Date: Jan 2013
Location: west chester, pa
Posts: 19,216
Likes: 0
Received 39 Likes
on
35 Posts
Year: 1999
Engine: 4.0
P0122 & P0123
At first I thought my transmission was gonna go...
The symptoms were, the transmission slipping and shifting up at 3,500 rpms, 5 second delay when shifting into reverse, and problems with downshifting while uphill.
I have always thought the previous owner had abused the transmission and caused the friction pads to be "worn out".
Then I was searching in here about options of rebuilding or whatever etc.
I saw one thread about problems with the transmission that sounded same as mine, so I read it, I was amazed to learn that the possibility that the fault is not to be blamed on the transmission.
Apparently throttle position sensor is possibly the culprit.
First thing I did, was to adjust and reset the TV cable and the transmission still performed the same.
Then I read about testing and trouble shooting the TPS.
The left wire is ground, so it read zero. The middle one read at 4.3 volts, and the right wire read at 5.5 volts, even with the key in ignition but not started.
I tried to moving the throttle valve and it went backwards... The middle wire went down to 3.2-3.4 volts when the throttle is fully open. I read that when its closed, it was supposed to be at .5 volts and when it's fully open, it was supposed to read at around 5 volts.
I found that interesting, then when I decided to stop working on the Cherokee, I went to start it up and saw that the check engine light was on, so I drove to advance auto to check the codes.
P0122 and P0123 was what I got...
Both codes point to the TPS as a culprit.
I have yet to buy the new one because frankly, I'm broke lol.
I hope when I replace the TPS, the transmission would be back to normal and give me back my MPGs lol.
I'm wondering if any one of you had similar experiences? What did u do, how did u check, etc etc.
The symptoms were, the transmission slipping and shifting up at 3,500 rpms, 5 second delay when shifting into reverse, and problems with downshifting while uphill.
I have always thought the previous owner had abused the transmission and caused the friction pads to be "worn out".
Then I was searching in here about options of rebuilding or whatever etc.
I saw one thread about problems with the transmission that sounded same as mine, so I read it, I was amazed to learn that the possibility that the fault is not to be blamed on the transmission.
Apparently throttle position sensor is possibly the culprit.
First thing I did, was to adjust and reset the TV cable and the transmission still performed the same.
Then I read about testing and trouble shooting the TPS.
The left wire is ground, so it read zero. The middle one read at 4.3 volts, and the right wire read at 5.5 volts, even with the key in ignition but not started.
I tried to moving the throttle valve and it went backwards... The middle wire went down to 3.2-3.4 volts when the throttle is fully open. I read that when its closed, it was supposed to be at .5 volts and when it's fully open, it was supposed to read at around 5 volts.
I found that interesting, then when I decided to stop working on the Cherokee, I went to start it up and saw that the check engine light was on, so I drove to advance auto to check the codes.
P0122 and P0123 was what I got...
Both codes point to the TPS as a culprit.
I have yet to buy the new one because frankly, I'm broke lol.
I hope when I replace the TPS, the transmission would be back to normal and give me back my MPGs lol.
I'm wondering if any one of you had similar experiences? What did u do, how did u check, etc etc.
Thread
Thread Starter
Forum
Replies
Last Post
BlueXJ
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
75
01-09-2024 02:54 PM
dohc91gli
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
4
01-29-2015 07:44 PM
MusicBiz
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
1
12-21-2014 06:54 PM
rklettke
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
4
03-05-2012 07:45 PM
1091x
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
5
09-23-2010 12:51 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)