Tps and TV cable

[asatxj]

First I did a search (noticed the new "already been asked" button good idea) and couldn't find the intel.
When ever I get off the highway (24 miles each day) I let off the gas and it downshifts too early then goes back to where it should be and the check engine light comes on. it drives normally after that and if I shut it off the ck engine light goes out. Can someone give me the procedure to adjust TPS and TV for a 91 4.0 Incidentally, the motor its self is 97 but TB and externals are 91. Other than this it runs great.

thanks all
asat

 

[asatxj]

Thanks for all the help! Too busy helping newbies figure out "which lift" I guess.

 

[90 xj]

First off do you have a dvom or some type of volt meter, or even acess to a scanner? if you do look in a repair manual to see whick wires to probe. i think that the 91+ have a 3 wire tps so you should hook the dvom to the connector of the tps and see what it reads. The manual should tell you which wires (like a b or c and a color) and what the voltage should be at idol and at wide open throttle. the tv cable should have some sort of button on the top push it and there is a slider that the cable runs in move it in or out then test drive it see if it gets better or worse, if you dont like the results move it the other way see if that makes a change.
jake

 

[8Mud]

I´ver got two manuals (Chiltons and haynes), a FSM and alldata. And still find questions that need to be asked.
I´ve got an 88 and a 96, believe the 96 is the same series as yours. If it is, there is no adjustment for the TPS. If it´s out of parameters, it should throw a code. www.jedi.com/obiwan/jeep/dtc.html has a pretty good write up on a quick test for stored codes.
The TV adjuster has a thumb sized tab, push it in and then push the center slide adjuster all the way in (the cable comes out of the end of the slide adjuster). Then push the gas pedal all the way to the floor, the slide adjuster will ratchet out, to the proper setting (same procedure for Chev, if you have a manual handy). TV cable adjusted. You can sometimes adjust the slide adjuster, one tooth in or out and it will hold the adjustment (fine adjusting). TV cable will allow downshift (passing gear) at (near) full throttle and also lowers the pump pressure some as the RPM´s go up, to avoid harsh shifts. You can also ratchet out the dajuster with your thumb on the throttle linkage, but the (newer) recommended procedure is to use the gas pedal.

 

[asatxj]

Thank you all!
Yep, I have the electronic test gear. If not my Brother in law is an Electrician, he has tools and then some!
I knew there were some answers out there if I asked!! I really don't want to drop for a new TPS but I guess you have to eventually and this one has nearly 230k on it so I guess I got my depreciation out of it.
I'll do the TV tomorrow after work.
Thanks again
asat

 

[explorer]

The cable on an AW4 has no effect on shift points as in some other auto's. It's only function is to vary line pressure in the trans. More throttle = more line pressure = firmer shift and vice-versa. The problem is more likely w/ the TPS.

Brian

 

[8Mud]

The cable on an AW4 has no effect on shift points as in some other auto's. It's only function is to vary line pressure in the trans. More throttle = more line pressure = firmer shift and vice-versa. The problem is more likely w/ the TPS.

Brian

The only tranny I really ever learned was the 727 and somewhat the 700R4. On both trans It said in the book, that the transmission valve, lowered the relative (relative being the key word) pump pressures, in relation to RPM, so the clutches don´t engauge too harshly.
Maybe I misread the passage or misunderstood. If I have it wrong, please somebody correct me and maybe supply some remeadial reading, never to old to learn something new.

 

[explorer]

The only tranny I really ever learned was the 727 and somewhat the 700R4. On both motors It said in the book, that the transmission valve, lowered the relative (relative being the key word) pump pressures, in relation to RPM, so the clutches don´t engauge too harshly.
Maybe I misread the passage or misunderstood. If I have it wrong, please somebody correct me and maybe supply some remeadial reading, never to old to learn something new.

Most throttle valve or kickdown cables do affect line pressure and shift timing. But on the AW4, the TCU controls all aspects of shift timing. The cable does nothing to affect what speed the tranny shifts into various gears. Try adjusting the cable from extreme soft to extreme firm. It will affect the harshness of the shift, and nothing else. Check out a factory manual, I'm pretty sure they don't even call it a TV cable. I can't remember what they call it, but not a TV cable. I'll see if I can dig up my AW4 manual anywhere to verify that.

 

[8Mud]

Pump pressure on some transmissions, affects downshifts and coverter lock up. Beleive your right about the TCU controling most functions.
Just looked at my troubleshooting list for the AW-4, first item for early, late or harsh downshifts is the throttle cable faulty. Next was an electrical malfunction. I´d be tempted to look at the speed sensor or the TPS, both should throw a code.
Never hurts to check the tranny throttle cable (transmission valve cable, TV cable), it often gets out of adjustment when messing with the intake and/or the throttle body.