Hi everyone. Been reading this forum for a couple months now. I just got a 02 KJ and I love it. I live in Venezuela... particularly in a small city callled Cumaná which has a lack of qualified car technicians when it comes to Chrysler (this is why I started fixing my cars in first place).
I got my KJ in August 23. It came with 171k miles. I changed all fluids, gaskets, seals and everything that could give me headaches. It has been running smoothly until yesterday. I was driving in the city (maybe at 20-25 mph) and suddenly it lose power, started shaking and turned on the MIL. I pulled over, turned it off, checked that everything was "in order" and thought of coming back home. It turned back on as usual but then when I shifted to D, it started running almost with no power (it felt like it was going neutral/D/neutral/D/neutral/D as I could hear the engine revving for a moment). Anyway, after 2min trying to make it to the safe side of the street I just turned it off and got towed back home.
At this point I did the auto diagnose to see if the dashboard showed me any error code. I only got the P0700. Also it was Neutral in each shift... P-R-N-D-2-1... they were all in neutral, except P in which the KJ was locked (as it should be).
Things to know:
- This KJ has a 45RFE trans.
- Fluid level is OK.
- Filters were installed 2 months ago.
- It's been working flawlessly until yesterday. No funny noises or nothing odd.
Once I got home I scanned it with one of these small scanners that can be used with any smartphone. I got these codes:
I cleared all the codes. Turned the KJ on and this time there was no MIL light but the scanner showed me this:
I got down and saw the Line Pressure Sensor harness was loose (I believe it was a cat that has been coming in and out my house at night). Anyways, I plugged it in and now I get now codes, however the I've got the same failure. Now, this morning I've got some interesting details from the scanner while reading the live data from the line pressure sensor.
When cold, the line pressure sensor sends 0,5v when is in neutral (P or N) and 2,5v when is in R or D (I read somewhere it's suppose to send 5v) and the shifts are actually made (it engages R or D). As the engine warms up, the 0,5v in P-N stays the same, but the pressure goes down along with the 2,5v until it gets to 0,5v and at that point it stays in neutral in every shift.
So for now I have 2 theories (as far as my knowledge let me make them
1- Bad Line pressure sensor. It got crazy and it's sending odds voltages.
2- Bad oil pump or loose filter which is causing the pressure drop as the engine warms up.
I have never worked on a transmission before but I am planning to get the oil pan down to have a look (I read that some times one of the filters falls off and whole trans get crazy), but before that I would like to know if there is something I'm missing.
Having 0 experience with transmissions I would like to have some lights from you guys, so any comment, idea, swear, etc is highly appreciated.
You can be sure I am super grateful in advance.
I got my KJ in August 23. It came with 171k miles. I changed all fluids, gaskets, seals and everything that could give me headaches. It has been running smoothly until yesterday. I was driving in the city (maybe at 20-25 mph) and suddenly it lose power, started shaking and turned on the MIL. I pulled over, turned it off, checked that everything was "in order" and thought of coming back home. It turned back on as usual but then when I shifted to D, it started running almost with no power (it felt like it was going neutral/D/neutral/D/neutral/D as I could hear the engine revving for a moment). Anyway, after 2min trying to make it to the safe side of the street I just turned it off and got towed back home.
At this point I did the auto diagnose to see if the dashboard showed me any error code. I only got the P0700. Also it was Neutral in each shift... P-R-N-D-2-1... they were all in neutral, except P in which the KJ was locked (as it should be).
Things to know:
- This KJ has a 45RFE trans.
- Fluid level is OK.
- Filters were installed 2 months ago.
- It's been working flawlessly until yesterday. No funny noises or nothing odd.
Once I got home I scanned it with one of these small scanners that can be used with any smartphone. I got these codes:
You must be registered for see images attach
I cleared all the codes. Turned the KJ on and this time there was no MIL light but the scanner showed me this:
You must be registered for see images attach
I got down and saw the Line Pressure Sensor harness was loose (I believe it was a cat that has been coming in and out my house at night). Anyways, I plugged it in and now I get now codes, however the I've got the same failure. Now, this morning I've got some interesting details from the scanner while reading the live data from the line pressure sensor.
When cold, the line pressure sensor sends 0,5v when is in neutral (P or N) and 2,5v when is in R or D (I read somewhere it's suppose to send 5v) and the shifts are actually made (it engages R or D). As the engine warms up, the 0,5v in P-N stays the same, but the pressure goes down along with the 2,5v until it gets to 0,5v and at that point it stays in neutral in every shift.
So for now I have 2 theories (as far as my knowledge let me make them
1- Bad Line pressure sensor. It got crazy and it's sending odds voltages.
2- Bad oil pump or loose filter which is causing the pressure drop as the engine warms up.
I have never worked on a transmission before but I am planning to get the oil pan down to have a look (I read that some times one of the filters falls off and whole trans get crazy), but before that I would like to know if there is something I'm missing.
Having 0 experience with transmissions I would like to have some lights from you guys, so any comment, idea, swear, etc is highly appreciated.
You can be sure I am super grateful in advance.