ok so here is the deal whin i left work today i got on the hwy as normal when my tranny down shifter into 3 and would not shift back so i pulled over and checked the fluid, the tcm connections as well as the the ones on the firewall and every thing looked good. so i got back on the road and it wouldnt shift passed 2 so i lemped it aways and then it shifted into 3 but would not shift into overdrive then whin i stop and went to take off agin the same thing. then i stoped once agin to call some one to tow me home and no one answerd so i was pissed off at this point so i spun out and it shifted into 2 but not 3 so i gunned it got the rpms up to 4grand when it shefted to 3 and then into overdrive just fine and ever since it has shifted fine but now at ideal it is gunning and 1.5grand in park put it in drive and it gos down to 1grand like normal any one know what the hell is going on?

o and I forgot to mention wile it was acting stupid and not shifting i could not shift it manualy

 

ok so i just took it out to c if its going to shift so i can take it to work tomorrow and the ideal is back to normal but it only shifts out 2 at 4.5rpms and will not shift into overdrive

 

Check your TPS. See post #8 here. https://www.cherokeeforum.com/f51/cr...x-tips-153657/ You don't state the year of your XJ but the TPS reads for both throttle and tranny on the older models. Erratic shift points is usually caused by a bad TPS and or connections.

Black89

 

Black89 beat me by about a minute! The AW4 transmission is electronic and one of the inputs that is critical comes from the "throttle position sensor". It is very important to proper shift points on the AW4. Here is more on how to verify this on your 1994 XJ. Good luck and keep us updated!
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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 accordingly 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 denied acceptable range causing the ECU to incorrectly fuel the engine. This is noticeable 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.

 

sorry i have a 94 and my tps is new i changed about 4 months back

 

No shortage of total crap engine management sensors out there. Where did you buy your TPS from? I buy my engine management sensors primarily only from Jeep. Aftermarket sensor are "hit and miss" with a whole heck of a lot of miss. Especially with the junk floating around on ebay.

Here is another thing to verify. Easy schmeezy.

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

 

Check it again I had a brand new BWD brand one go bad after only 2 weeks. Then a month later my TCU went bad and was causing TC Lock up in first and second. I had a spare TCU from a 90' and it fixed my issue. Retest your TCU and verify that it's working. Hook up your volt meter and check the values first then sweep it slowly while you watch the values change on the meter making sure it changes and there are no dead spots. It seems the best TPS are either the spendy OEM's or the ones from napa.

Black89

 

tjwalker thanks for the info and i got my tps from orilys becouse no dealer had it here and i could not wait for it to come in and i know all to well about ****y after market parts. i have had a problem with the ideal ever since the first rain after i installed hood vent so im thinking i need to do some water profin

 

O'Reilly's is where mine came from. At least they have the 1 yr. warranty on them.

Black89

 

lol yeah

 

Test that sensor, do the fix tjwalker posted, and check your grounds, which is #1 in that link Black89 conveniently posted.

 

thank yall for all the help it was a bad tbs

 

BINGO!

Black89

 

yes thank u sir