Slow shifting 98 XJ 4.0

I have a 98 XJ 4.0 that is shifting late, for example it won't shift into overdrive if I don't let my foot of the gas.

I've adjusted the TV cable and replaced the TPS sensor.

Any suggestions?

here's a video of trying to get in overdrive, eventually I let off the gas.
https://streamable.com/t1dt7

Did you install a genuine Jeep TPS or some crappy Chinese clone TPS ? If TV cable fine tuning does not make it perform correctly, suspect that the TPS may be faulty.

The TV cable can be adjusted to make the transmission shift sooner. Adjust the TV cable per the Service Manual instructions. Mark the cable housing and then press the button and slide the cable either out or in slightly until it shifts how you want it to. I adjusted my 98 for quicker downshifts.

Got a Crown Automotive 4874371A.
Will have another go with the TV cable, thanks!

Tim_MN said:

The TV cable can be adjusted to make the transmission shift sooner.

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Just to clarify a bit, the trans computer decides when to shift based on speeds and the TPS sensor. The TV cable controls the hydraulic pressure, and thus the firmness of the shift. If it's adjusted wrong then it will shift slowly or not at all, or very hard. My first suspect would be the TPS or it's wiring, but you might also have a bad t/c lockup solenoid or bad t/c.

The trans computer also uses the brake switch and the NSS to decide when to lock/unlock the torque converter - something many people incorrectly refer to as overdrive.

I have the same issue, no matter how I adjust the cable it doesn't respond. and on cruise control it is impossible to get into Overdrive, the engine will be always be at least 3000 RPM

SuperDOS said:

Got a Crown Automotive 4874371A.

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This is the exact definition of crappy low budget parts. Installing a genuine Jeep TPS should solve the problem.

Most auto parts stores sell cheap crappy Chinese made parts, some that even come with a "Lifetime Warranty". These parts are poorly manufactured and/or made from inferior materials. They are often out of specification, or even failed, right out of the box. The ones that are not faulty many times will have a short service life before they fail. Always buy top quality replacement parts and genuine Jeep engine sensors. Numerous threads detail long and frustrating searches for a "problem" that ended up being cured simply with genuine Jeep repair parts.

Cheap parts are cheap for a reason.

Well I wouldn't call Crown parts cheap, cheaper yes.

Will do a more thorough check of the TPS and TV cable.

Measured with multimeter and I think the tps is ok, though at idle it's 1.3 volts. Took the off the tps connector cable and measure the signal wire (middle one) and it said 5 volt (not the contant wire) which is very weird. What could cause it to send 5 volts at idle.

The PCM supplies approximately 5 volts to the TPS and to all the other OBD engine sensors. The TPS output voltage (input signal to the PCM) represents the throttle blade position. The PCM receives an input signal voltage from the TPS. It is best 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 5volts. This will vary in an approximate range of from .25 volts at minimum throttle opening (idle), to 4.8 volts at WOT wide open throttle.

With a 1.3 volts reading at idle, I would be shopping for a genuine Jeep TPS.

Thanks will probably look for a new mopar TPS just to rule that out.

Ok I finally got a mopar tps sensor. Not sure if there's any difference. I used my elm obd2 to read the tps and it says 17% open on idle the old sensor said 14%. Shouldn't ir be zero % when just idling?

SuperDOS said:

Ok I finally got a mopar tps sensor. Not sure if there's any difference. I used my elm obd2 to read the tps and it says 17% open on idle the old sensor said 14%. Shouldn't ir be zero % when just idling?

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The throttle is never completely closed. Same reason the "closed throttle" TPS signal should read as .2-.5 volts. You're 1.3 volts sounds high (you were measuring between the signal ground and the TPS signal, and not to chassis ground?)