Weird Transmission Problem...

[Lee21490]

Where to start..

 

For the last few days when going over 40~ my transmission keeps shifting into overdrive / 4th whatever you call it, Then straight back to third back and forth

 

Then i started to notice today, that whenever i give it a bit of gas to speed up quickly, when i hit 30-35 it auto shifts to 4th untill i let off the gas & it shifts back down to 3rd Even when i'm in the 1-3 position on the shifter

 

 

 

How is it even possible to shift into 4th when you're in the 1-3rd position...

 

 

Transmission is out of a 95 4.0l Cherokee, In a 86 comanche

 

 

Sorry if i made this confusing, I'm dead tired lol

[cruiser54]

Your torque converter is most likely locking and unlocking, not shifting between gears. What postion is your Power/ Comfort switch in?

 

Ever done this?

 

http://www.cherokeeforum.com/f2/free-quick-fix-41821/

 

TPS could also be an issue. Do the above stuff first.

[Lee21490]

Your torque converter is most likely locking and unlocking, not shifting between gears. What postion is your Power/ Comfort switch in?

 

Ever done this?

 

http://www.cherokeef...uick-fix-41821/

 

TPS could also be an issue. Do the above stuff first.

 

Your link brings up a "Page not found"

 

Power comfort switch?

 

/e

 

Hmm didnt know it had that, I have the switch but all the writing around it was gone so i thought it was just a dead switch (I wasnt the one that swapped the 4.0L / dash)

 

 

/e#2

 

According to some googling.. 92+ Xj's didnt have the switch, and were in power mode 100%

[Geonovast]

I would tackle the TPS first.

[HOrnbrod]

Before any of the above, try adjusting the Throttle Valve cable (commonly called the kickdown cable) first. If maladjusted it will cause your AW4 shifting points to be all over the place. Takes no tools and about five minutes to do.

 

 

1: Push in and hold the release button

2: While holding in release button, push "conduit" in as far as it will go

3: Release button

4: Rotate throttle to WOT, some people do this with the gas pedal. Others do it from the engine compartment.

5: Hold at WOT for a few seconds, cable should ratchet out a click or two.

6: Your TV cable should now be properly adjusted.

[Lee21490]

Before any of the above, try adjusting the Throttle Valve cable (commonly called the kickdown cable) first. If maladjusted it will cause your AW4 shifting points to be all over the place. Takes no tools and about five minutes to do.

 

 

1: Push in and hold the release button

2: While holding in release button, push "conduit" in as far as it will go

3: Release button

4: Rotate throttle to WOT, some people do this with the gas pedal. Others do it from the engine compartment.

5: Hold at WOT for a few seconds, cable should ratchet out a click or two.

6: Your TV cable should now be properly adjusted.

 

Just did this & drove around a bit.

Still locks / unlocks the torque converter over and over

I would tackle the TPS first.

 

How do i test if mines bad?

[Geonovast]

If cruiser54 doesn't pop in with the procedure, PM him. I know all you need is a volt meter to test it at closed and WOT, but I don't know the ranges, and he's got the test procedures for the sensors on speed dial.

[cruiser54]

If the Power/Comfort switch is unplugged, you are in the Comfort mode. Not good. To restore Power mode, run a jumper wire between the tan wire and the striped wire in the 3-wire connector for the switch. Leave the black one alone.

 

Here's how to check the YPS. Be sure to use the instructions for the square plug on the trans side.

 

 

RENIX TPS ADJUSTMENT

Before attempting to adjust your TPS be sure the throttle body has been recently cleaned. It's especially important that the edges of the throttle butterfly are free of any carbon build-up.

IMPORTANT NOTE: With the Key OFF, and using the positive (red) lead of your ohmmeter, probe the B terminal of the flat 3 wire connector of the TPS. The letters are embossed on the connector itself. Touch the black lead of your meter to the negative battery post. Wiggle the wiring harness where it parallels the valve cover and also over near the MAP sensor on the firewall. If you see more than 1 ohm of resistance, or fluctuation in your ohms reading, some modifications to the sensor ground harness will be necessary. The harness repair must be performed before proceeding. I can provide an instruction sheet for that if needed.

MANUAL TRANSMISSION:

RENIX manual transmission equipped XJs have only a flat three-wire TPS mounted on the throttle body and it provides data input to the ECU. It has three wires in the connector and they're clearly embossed with the letters A, B, and C. Wire "A" is positive. Wire "B" is ground. Key ON, measure voltage from "A" positive to "B" ground by back-probing the connectors. Note the voltage reading--this is your REFERENCE voltage. Key ON, back-probe the connector at wires "B" and "C". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be seventeen percent of your REFERENCE voltage. For example: 4.82 volts X .17=.82 volts. Loosen both T-20 Torx screws attaching the TPS to the throttle body and rotate the TPS until you

have achieved your desired output voltage. Tighten the screws carefully while watching to see that your output voltage remains where it is supposed to be. If you can't achieve the correct output voltage, replace the TPS and start over.

Sometimes, after adjusting your TPS the way outlined above, you may experience a high idle upon starting. If that happens, shut the engine off and reconnect your probes to B and C. Start the engine and while watching your meter, turn the TPS clockwise until the idle drops to normal and then rotate it back counterclockwise to your desired output voltage.

AUTOMATIC TRANSMISSION: RENIX automatic transmission equipped XJs have a TPS with two connectors. There is a flat three-wire connector, same as the manual transmission vehicles have, and it is tested the same as the manual transmission equipped vehicles, as outlined above—FOR ALL ENGINE MANAGEMENT RELATED ISSUES.

However, the automatic TPS also has a square four-wire connector, clearly embossed with the letters A,B,C, and D. It only uses three wires and provides information to the Transmission Control Module. THIS SQUARE FOUR WIRE CONNECTOR IS USED FOR TRANSMISSION/SHIFTING RELATED ISSUES ONLY. Key ON, measure voltage between "A" positive and "D" ground. Note the voltage. This is your REFERENCE voltage. Back-probe the connector at wires "B" and "D". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be eighty-three percent of your REFERENCE voltage. For example 4.8 volts X .83=3.98 volts. Adjust the TPS until you have achieved this percentage. If you can't, replace the TPS and start over. So, if you have an automatic equipped XJ your TPS has two sides--one side feeds the ECU, and the other side feeds the TCU.

FOR AUTOMATIC TRANSMISSION RELATED ISSUES: Check the square four-wire connector side of the TPS.

If you have ENGINE ISSUES check the flat three-wire connector side of the TPS.

For those with a MANUAL TRANSMISSION--the TPS for the manual transmission XJs is stupid expensive. You can substitute the automatic transmission TPS which is reasonably priced.

Revised 09-22-2012

[Lee21490]

If the Power/Comfort switch is unplugged, you are in the Comfort mode. Not good. To restore Power mode, run a jumper wire between the tan wire and the striped wire in the 3-wire connector for the switch. Leave the black one alone.

 

Here's how to check the YPS. Be sure to use the instructions for the square plug on the trans side.

 

 

RENIX TPS ADJUSTMENT

Before attempting to adjust your TPS be sure the throttle body has been recently cleaned. It's especially important that the edges of the throttle butterfly are free of any carbon build-up.

IMPORTANT NOTE: With the Key OFF, and using the positive (red) lead of your ohmmeter, probe the B terminal of the flat 3 wire connector of the TPS. The letters are embossed on the connector itself. Touch the black lead of your meter to the negative battery post. Wiggle the wiring harness where it parallels the valve cover and also over near the MAP sensor on the firewall. If you see more than 1 ohm of resistance, or fluctuation in your ohms reading, some modifications to the sensor ground harness will be necessary. The harness repair must be performed before proceeding. I can provide an instruction sheet for that if needed.

MANUAL TRANSMISSION:

RENIX manual transmission equipped XJs have only a flat three-wire TPS mounted on the throttle body and it provides data input to the ECU. It has three wires in the connector and they're clearly embossed with the letters A, B, and C. Wire "A" is positive. Wire "B" is ground. Key ON, measure voltage from "A" positive to "B" ground by back-probing the connectors. Note the voltage reading--this is your REFERENCE voltage. Key ON, back-probe the connector at wires "B" and "C". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be seventeen percent of your REFERENCE voltage. For example: 4.82 volts X .17=.82 volts. Loosen both T-20 Torx screws attaching the TPS to the throttle body and rotate the TPS until you

have achieved your desired output voltage. Tighten the screws carefully while watching to see that your output voltage remains where it is supposed to be. If you can't achieve the correct output voltage, replace the TPS and start over.

Sometimes, after adjusting your TPS the way outlined above, you may experience a high idle upon starting. If that happens, shut the engine off and reconnect your probes to B and C. Start the engine and while watching your meter, turn the TPS clockwise until the idle drops to normal and then rotate it back counterclockwise to your desired output voltage.

AUTOMATIC TRANSMISSION: RENIX automatic transmission equipped XJs have a TPS with two connectors. There is a flat three-wire connector, same as the manual transmission vehicles have, and it is tested the same as the manual transmission equipped vehicles, as outlined above—FOR ALL ENGINE MANAGEMENT RELATED ISSUES.

However, the automatic TPS also has a square four-wire connector, clearly embossed with the letters A,B,C, and D. It only uses three wires and provides information to the Transmission Control Module. THIS SQUARE FOUR WIRE CONNECTOR IS USED FOR TRANSMISSION/SHIFTING RELATED ISSUES ONLY. Key ON, measure voltage between "A" positive and "D" ground. Note the voltage. This is your REFERENCE voltage. Back-probe the connector at wires "B" and "D". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be eighty-three percent of your REFERENCE voltage. For example 4.8 volts X .83=3.98 volts. Adjust the TPS until you have achieved this percentage. If you can't, replace the TPS and start over. So, if you have an automatic equipped XJ your TPS has two sides--one side feeds the ECU, and the other side feeds the TCU.

FOR AUTOMATIC TRANSMISSION RELATED ISSUES: Check the square four-wire connector side of the TPS.

If you have ENGINE ISSUES check the flat three-wire connector side of the TPS.

For those with a MANUAL TRANSMISSION--the TPS for the manual transmission XJs is stupid expensive. You can substitute the automatic transmission TPS which is reasonably priced.

Revised 09-22-2012

 

There is no power / comfort switch. They stopped putting them in in 92, And the dash / engine / tranny is out of a 95

 

 

Also i read around a bit and people were saying you can just hook up the torque converter to a switch to lock whenever you want with a simple splice, Can anyone link me to a guide / tell me what wires to splice? Think that will be the easiest way to solve my problem.

 

/e nvm found a few write ups on it, Going to run to the store & get a switch / wire.

 

Wish me luck!

[HOrnbrod]

Have you checked the torque converter lock-up solenoid coil resistance yet? All the switch does is manually makes/breaks the lock-up solenoid. If the solenoid is bad the switch will do you no good.

[Lee21490]

Have you checked the torque converter lock-up solenoid coil resistance yet? All the switch does is manually makes/breaks the lock-up solenoid. If the solenoid is bad the switch will do you no good.

 

 

Spliced in the switch, Works fine now.

 

:3