HELP MY XJ trans issue
#16
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Year: 1992
Model: Cherokee
Engine: 4.0L L6 PowerTech (stock)
We're you ever able to test the engine's response to depressing the gas pedal prior to installing the functional/replacement transmission? Was the previous transmission even drivable?
If you think that it is engine side, then you can spray brake cleaner on the pivoting mechanism outside of the throttle body, spray throttle body/carburetor cleaner inside of the throttle body, check you linkages, ensure that your air filter is clean. Basically, ensure that everything for a tune-up is fine. Maybe the engine is responding roughly to the high shift in gearing because it isn't "tuned" well.
If you think that it is engine side, then you can spray brake cleaner on the pivoting mechanism outside of the throttle body, spray throttle body/carburetor cleaner inside of the throttle body, check you linkages, ensure that your air filter is clean. Basically, ensure that everything for a tune-up is fine. Maybe the engine is responding roughly to the high shift in gearing because it isn't "tuned" well.
#17
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Year: 1995 RHD
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Engine: 4.0l
I'll you can probe the wires to the transmission to check for solenoid resistances but I'll have to post that later.
#18
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Year: 1989
Model: Cherokee (XJ)
Engine: 4.0
When manually selecting 1-2, 3 and D do you feel all gear changes? I had 1st to OD on mine and Solenoid #2 was dead as it plays part in controling 2nd and 3rd.
I'll you can probe the wires to the transmission to check for solenoid resistances but I'll have to post that later.
I'll you can probe the wires to the transmission to check for solenoid resistances but I'll have to post that later.
#19
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Year: 1995 RHD
Model: Cherokee (XJ)
Engine: 4.0l
All solenoids should read between 11-15 ohms. To check this you'll need a multimeter or ohm meter. Any corrosion in the connections or breaks in the wiring could show a high resistance or open circuit so those possibilities should be checked out.
When I tested mine, I had to use a body ground for one of my probes and then the other on the wiring connector. The pin-out diagram is for the wiring loom connector but I have made it easier to see which pins to probe. The multimter images show my readings for solenoid #1 then solenoid #2.
When I tested mine, I had to use a body ground for one of my probes and then the other on the wiring connector. The pin-out diagram is for the wiring loom connector but I have made it easier to see which pins to probe. The multimter images show my readings for solenoid #1 then solenoid #2.
#20
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Year: 1989
Model: Cherokee (XJ)
Engine: 4.0
All solenoids should read between 11-15 ohms. To check this you'll need a multimeter or ohm meter. Any corrosion in the connections or breaks in the wiring could show a high resistance or open circuit so those possibilities should be checked out.
When I tested mine, I had to use a body ground for one of my probes and then the other on the wiring connector. The pin-out diagram is for the wiring loom connector but I have made it easier to see which pins to probe. The multimter images show my readings for solenoid #1 then solenoid #2.
When I tested mine, I had to use a body ground for one of my probes and then the other on the wiring connector. The pin-out diagram is for the wiring loom connector but I have made it easier to see which pins to probe. The multimter images show my readings for solenoid #1 then solenoid #2.
#21
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Year: 96
Model: Cherokee (XJ)
Engine: 4.0
All solenoids should read between 11-15 ohms. To check this you'll need a multimeter or ohm meter. Any corrosion in the connections or breaks in the wiring could show a high resistance or open circuit so those possibilities should be checked out.
When I tested mine, I had to use a body ground for one of my probes and then the other on the wiring connector. The pin-out diagram is for the wiring loom connector but I have made it easier to see which pins to probe. The multimter images show my readings for solenoid #1 then solenoid #2.
When I tested mine, I had to use a body ground for one of my probes and then the other on the wiring connector. The pin-out diagram is for the wiring loom connector but I have made it easier to see which pins to probe. The multimter images show my readings for solenoid #1 then solenoid #2.
http://gojeep.willyshotrod.com/HowtoAutoSwitch.htm
lots of good info on that link, and the guys whole website is excellent
#22
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Keep in mind that the TCU grounds at the engine dipstick tube stud and that the 2 connectors near the tranny dipstick can be corroded inside causing this issue.
#24
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#26
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#27
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Year: 1992
Model: Cherokee
Engine: 4.0L L6 PowerTech (stock)
Throttle position sensor is primary suspect. It is directly involved with shifting characteristics. More below.
---------------------------------------------
The throttle position sensor is connected to the throttle shaft on the throttle body. It sends throttle valve angle information to the PCM. The PCM uses this information to determine how much fuel the engine needs. The TPS is really just a simple potentiometer with one end connected to 5 volts from the PCM and the other to ground. A third wire is connected to the PCM. As you move the accelerator pedal with your foot, the output of the TPS changes. At a closed throttle position, the output of the TPS is low, about a half a volt. As the throttle valve opens, the output increases so that, at wide open throttle, the output voltage should be above 3.9 volts. Testing can be performed with an electrical meter. Analog meter is best. You are looking for a smooth sweep of voltage throughout the entire throttle band. While slowly opening and closing the throttle, take note to the movement of the voltmeter needle. There should be a direct relationship between the needle motion to the motion of the throttle. If at anytime the needle moves abruptly or inconsistently with the movement of the throttle, the TPS is bad
You should have 5 volts going into the TPS. At idle, TPS output voltage must be greater than 200 millivolts. At wide open throttle (WOT), TPS output voltage must be less than 4.8 volts.. The best is to use an analog meter (not digital) to see if the transition from idle to WOT is smooth with no dead spots. With your meter set for volts, put the black probe on a good ground like your negative battery terminal. With the key on, engine not running, test with the red probe of your meter (install a paper clip into the back of the plug of the TPS) to see which wire has the 5 volts. One of the other wires should show .26V (or so). The other wire will be the ground and should show no voltage. Move the throttle and look for smooth meter response up to the 4.49 at WOT.
Perform the test procedure again and wiggle and/or tap on the TPS while you watch the meter. If you notice any flat spots or abrupt changes in the meter readings, replace the TPS.
The TPS is sensitive to heat, moisture and vibration leading to the failure of some units. The sensor is a sealed unit and cannot be repaired only replaced. A TPS may fail gradually leading to a number of symptoms which can include one or more of the following: -
NOTE: The throttle position sensor is also DIRECTLY involved with transmission shifting characteristics! It should be verified early in the troubleshooting process, when a transmission issue is suspected!
• Poor idle control: The TPS is used by the ECU to determine if the throttle is closed and the car should be using the Idle Air Control Valve exclusively for idle control. A fault TPS sensor can confuse the ECU causing the idle to be erratic or "hunting".
• High Idle Speed: The TPS may report faulty values causing the engine idle speed to be increased above normal. This is normally found in conjunction with a slow engine return to idle speed symptom.
• Slow engine return to idle: A failing TPS can report the minimum throttle position values incorrectly which can stop the engine entering idle mode when the throttle is closed. Normally when the throttle is closed the engine fuel injectors will be deactivated until a defined engine RPM speed is reached and the engine brought smoothly to idle speed. When failing a TPS will not report the throttle closed and fueling will continue causing the engine to return to idle very slowly.
• Engine Hesitation on Throttle Application: The TPS is also used by the ECU to determine if the driver has applied the throttle quicker than the Manifold Air Pressure sensor can read. The fueling is adjusted acordingly to cope with the sudden increase in air volume, however a faulty sensor can cause the ECU to ignore this data and the engine will "hesitate" when applying the throttle. In extreme cases with the engine at idle, a sudden application of full throttle can stall the engine.
• Engine Misfire: A fault TPS can report values outside the deined acceptable range causing the ECU to incorrectly fuel the engine. This is noticable as a slight misfire and can trigger the misfire detection software and/or Malfunction Indicator Lamp (MIL) light on the dashboard. Extreme cases can cause excessing misfires resulting in one or more cylinders being shut down to prevent engine and catalytic converter damage.
---------------------------------------------
The throttle position sensor is connected to the throttle shaft on the throttle body. It sends throttle valve angle information to the PCM. The PCM uses this information to determine how much fuel the engine needs. The TPS is really just a simple potentiometer with one end connected to 5 volts from the PCM and the other to ground. A third wire is connected to the PCM. As you move the accelerator pedal with your foot, the output of the TPS changes. At a closed throttle position, the output of the TPS is low, about a half a volt. As the throttle valve opens, the output increases so that, at wide open throttle, the output voltage should be above 3.9 volts. Testing can be performed with an electrical meter. Analog meter is best. You are looking for a smooth sweep of voltage throughout the entire throttle band. While slowly opening and closing the throttle, take note to the movement of the voltmeter needle. There should be a direct relationship between the needle motion to the motion of the throttle. If at anytime the needle moves abruptly or inconsistently with the movement of the throttle, the TPS is bad
You should have 5 volts going into the TPS. At idle, TPS output voltage must be greater than 200 millivolts. At wide open throttle (WOT), TPS output voltage must be less than 4.8 volts.. The best is to use an analog meter (not digital) to see if the transition from idle to WOT is smooth with no dead spots. With your meter set for volts, put the black probe on a good ground like your negative battery terminal. With the key on, engine not running, test with the red probe of your meter (install a paper clip into the back of the plug of the TPS) to see which wire has the 5 volts. One of the other wires should show .26V (or so). The other wire will be the ground and should show no voltage. Move the throttle and look for smooth meter response up to the 4.49 at WOT.
Perform the test procedure again and wiggle and/or tap on the TPS while you watch the meter. If you notice any flat spots or abrupt changes in the meter readings, replace the TPS.
The TPS is sensitive to heat, moisture and vibration leading to the failure of some units. The sensor is a sealed unit and cannot be repaired only replaced. A TPS may fail gradually leading to a number of symptoms which can include one or more of the following: -
NOTE: The throttle position sensor is also DIRECTLY involved with transmission shifting characteristics! It should be verified early in the troubleshooting process, when a transmission issue is suspected!
• Poor idle control: The TPS is used by the ECU to determine if the throttle is closed and the car should be using the Idle Air Control Valve exclusively for idle control. A fault TPS sensor can confuse the ECU causing the idle to be erratic or "hunting".
• High Idle Speed: The TPS may report faulty values causing the engine idle speed to be increased above normal. This is normally found in conjunction with a slow engine return to idle speed symptom.
• Slow engine return to idle: A failing TPS can report the minimum throttle position values incorrectly which can stop the engine entering idle mode when the throttle is closed. Normally when the throttle is closed the engine fuel injectors will be deactivated until a defined engine RPM speed is reached and the engine brought smoothly to idle speed. When failing a TPS will not report the throttle closed and fueling will continue causing the engine to return to idle very slowly.
• Engine Hesitation on Throttle Application: The TPS is also used by the ECU to determine if the driver has applied the throttle quicker than the Manifold Air Pressure sensor can read. The fueling is adjusted acordingly to cope with the sudden increase in air volume, however a faulty sensor can cause the ECU to ignore this data and the engine will "hesitate" when applying the throttle. In extreme cases with the engine at idle, a sudden application of full throttle can stall the engine.
• Engine Misfire: A fault TPS can report values outside the deined acceptable range causing the ECU to incorrectly fuel the engine. This is noticable as a slight misfire and can trigger the misfire detection software and/or Malfunction Indicator Lamp (MIL) light on the dashboard. Extreme cases can cause excessing misfires resulting in one or more cylinders being shut down to prevent engine and catalytic converter damage.
#28
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Year: 1992
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Engine: 4.0L L6 PowerTech (stock)
This may be blasphemy.
https://www.naxja.org/forum/showthread.php?t=1053970
"The 1987-1996 NSS only has inputs to the TCU for the shifter being in (1-2) or (D). The later ones have an extra input line for (3). In theory you could use the later version if you cut and splice just the wires you need.
Not relevant for NSS swapping, but the later TCUs also seem to have an input for the reverse lights that the earlier setup didn't have.
On putting a pre-98 AW4 into a 98+, I wonder if you could get away with installing a 97 TCU that didn't care about the front sensor and might talk to the PCM enough to avoid a check-engine light.."
Also, "What does this mean for swapping (4wd specific)?
If you have a 1987-1990 XJ:
To be honest I've more experience with driving manual transmissions than automatic transmission.
https://www.naxja.org/forum/showthread.php?t=1053970
"The 1987-1996 NSS only has inputs to the TCU for the shifter being in (1-2) or (D). The later ones have an extra input line for (3). In theory you could use the later version if you cut and splice just the wires you need.
Not relevant for NSS swapping, but the later TCUs also seem to have an input for the reverse lights that the earlier setup didn't have.
On putting a pre-98 AW4 into a 98+, I wonder if you could get away with installing a 97 TCU that didn't care about the front sensor and might talk to the PCM enough to avoid a check-engine light.."
Also, "What does this mean for swapping (4wd specific)?
If you have a 1987-1990 XJ:
- 1987-1990 AW4s are bolt-in.
- 1990.5-1996 are bolt-in as long as you swap input gears in your transfer case to a 23 spline, or swap the transfer case as well. Remember that NP231 input gear cuts changed in 94 or 95 and that the rear output of the transfer case changed from 95 to 96 when selecting a donor.
- 1997 are bolt-in if you follow the transfer case input gear info from 1990.5-1996 and also splice the wiring harness connector. All it takes is 5 butt-splice crimp terminals and a few minutes, so don't worry about it, if you can handle wiring some fog lights you can handle this. You may need to run a new set of wires for your transfer case indicator lamp connector if you have an NP231 (I haven't had a chance to verify this, will check next time a friend of mine drops by with his RENIX.)
- 1998-2001 require more work. All the transfer case input gear info from 1990.5-1997 applies, on top of that, the sensors have changed! You can either build the circuit given here by lawsoncl or swap the transmission tailhousing, sensor drive rotor, and output speed sensor as shown here by Frank Z to make this work."
To be honest I've more experience with driving manual transmissions than automatic transmission.
#29
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Year: 1995 RHD
Model: Cherokee (XJ)
Engine: 4.0l
The lock-up solenoid won't be causing the gears to not engage. At this point I don't know what else to suggest as my AW4 knowledge is limited to the issue I had.
#30
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Year: 1989
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okay so i purchased the kit of 3 solenoids hope this is the problem thanks to everyone who gave their input in my situation putting them in tonight so i'll let you know