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Overdrive Not working Right When Warm

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Old 05-30-2013, 02:45 PM
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Default Overdrive Not working Right When Warm

After my jeep warms up overdrive will engage at 35 but as soon as I go to try and hold a steady speed say like 50-55mph it act like it disengages ie. rpms go up and jeep slows down alot. If I slightly move the gas peddle down overdrive fully engages but picks up speed. Im only moving the gas pedal a hair to get it engaged but it still accels at a decent rate. I have new fluid in the trans have adjusted the kick down cable and checked my tps. Everything is correct according to cruisers write up. What else can be causing this?
Old 05-30-2013, 06:08 PM
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I think that's your torque converter locking and unlocking. Power or Comfort mode on the dash switch?
Old 05-30-2013, 07:39 PM
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Originally Posted by cruiser54
I think that's your torque converter locking and unlocking. Power or Comfort mode on the dash switch?
Its off normally but when the rare occasion comes that it is on it wont engage od until almost 65
Old 05-30-2013, 08:54 PM
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Trans side of TPS may be bad.
Old 05-30-2013, 10:19 PM
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Originally Posted by cruiser54
Trans side of TPS may be bad.
How can that be I checked it per your write up. Was the first thing I did because I was worried that may have been the case along with my idle issue
Old 05-30-2013, 11:09 PM
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Originally Posted by Slim357
How can that be I checked it per your write up. Was the first thing I did because I was worried that may have been the case along with my idle issue

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
Old 05-31-2013, 10:42 AM
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Originally Posted by cruiser54

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
I have done this and everything checked out
Old 05-31-2013, 03:22 PM
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Originally Posted by Slim357
I have done this and everything checked out
Just making sure. I field a buttload of posts and PMs. I can't keep up with everyone.
Old 05-31-2013, 03:37 PM
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Originally Posted by cruiser54

Just making sure. I field a buttload of posts and PMs. I can't keep up with everyone.
Its all good I know your a busy man on here bro. Any other ideas of what might be going on? Hoping I dont need a trans put in but might be better to do it.
Old 05-31-2013, 03:39 PM
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Originally Posted by Slim357
Its all good I know your a busy man on here bro. Any other ideas of what might be going on? Hoping I dont need a trans put in but might be better to do it.
Don't jump on that bandwagon just yet. Ever do the sensor ground test or upgrade?

Trans connector refreshing?
Old 05-31-2013, 03:51 PM
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Originally Posted by cruiser54

Don't jump on that bandwagon just yet. Ever do the sensor ground test or upgrade?

Trans connector refreshing?
Did the test and again everything checked out. Not trying to jump on the band wagon as I need to save money where I can Im just worried about hitting the beach with the way the trans is acting. Cant really afford to be putting a new trans in the jeep after going on the beach a few times with it
Old 05-31-2013, 04:36 PM
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Just do the trans connector refreshing anyway.

#10 in my Tips
Old 06-01-2013, 12:09 AM
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Originally Posted by cruiser54
Just do the trans connector refreshing anyway.

#10 in my Tips
Ok Ill give it a shot
Old 06-04-2013, 11:07 AM
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Well the connections at the dip stick tube are nice and clean havent got around to checking the tcm connections yet
Old 06-04-2013, 06:05 PM
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Originally Posted by Slim357
Well the connections at the dip stick tube are nice and clean havent got around to checking the tcm connections yet
So what's the hold up? Can't spare 5 minutes under the hood? JK.


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