Engine/Transmission (1994 - 1998) Tps

[ndurbin]

Tps/Kick down cable adjustment

First off I'll explain my problem. no lockup of TC in 3rd gear and at about 70-75 if you push the pedal down to pass someone the TC unlocks and then locks back up after acouple fo seconds.



Second, the fixes I have tried. I've cleaned the connections with contact cleaner. I'm going to go out and use my volt meter to test the voltages of the TPS.



I read up on the noise filter on the DTT site. It says with problems between 40-60. I haven't had the problem in that range just at about 70-75.



TIA

Nathan

 

[Joe G.]

I not sure what you mean by no lockup in 3rd. If OD is not locked out then it will not lockup in 3rd. If OD is locked out then it wil.



This one does not really sound like a TPS problem. It sounds more like a kick down cable adjustment problem.

 

[ndurbin]

I was under the impression that the TC was to lock up in 3rd gear.



The TPS had 4. 43V with the key on. I didn't have any wire or paper clips to do the second part of the test.



How do you adjust the kick down cable?



Thanks

Nathan



Edit: Just did a search on kick down cable adjustment. And understand now that the TC shouldn't lock up in 3rd. I just had the Blumenthal trans. installed by the dealer and got it back today. but these problems where there before the trans was replaced.

 

[Joe G.]

A TPS problem is usually flaky behaviour like locking and unlocking the TCC quickly or something like that. Your symptoms seem to be stable.



If OD is locked out you should have 1-2, 2-3, and lockup shifts. If OD is not locked out you should have 1-2, 2-3, 3-OD, and lockup shifts.



There are three cables to the throttle levers near the TPS; throttle pedal, cruise control, and kick down. The kick down cable is the lower one. It goes thru a plastic cube shaped piece that fits in bracket. There is a bulge on one side of the cube. The other three sides are flat. The bulge is a housing for a spring. The flat side opposite the bulge is a button. I use a small c-clamp to press and hold the button for adjustment. Before doing any adjustment make sure the cable and housing are in good condition. Also make sure the spring on the throttle lever on the transmission is not broken or missing.



The adjustment is made by moveing the pointed end where the cable comes out of the cable in or out of the cube. The cable is not really adjustable. The cable housing is what is adjusted. So making the cable housing longer is the same as making the cable shorter and vice versa. Measure how much the pointed end of the cable housing protrudes before moving anything so if you get it messed up you can put it back like it was. The correct adjustment should be so there is about 1/8" movement remaining in the kick down lever on the transmission when the throttle pedal is at wide open throttle. You may want to start with it there and fine tune it from that adjustment until you get it like you want it.

 

[ndurbin]

Just went out and checked the kick down cable. The spring is there on the throttle lever. but there is no button on the oppistie side of the bulge. theres a rough spot on the side the button is suppose to be on. maybe the button got broke off?

 

[Joe G.]

The button is the flat place opposite the bulge. If you press it with your finger you can feel it press in. The problem is that you can't really adjust the cable and hold the button in at the same time. Need three hands. I use a small c-clamp to hold button. The anvil part of the clamp is on the bulge and the screw end of the clamp is on the flat place.

 

[shendren]

just went thru the whole thing myself. several times. bills capacitors didn't work.



my truck was going in and out of lock up at 50mph+. especially under light throttle. you need to be checking your voltages going down the road with the dvm in the truck with you. mine were flucuating wildly. i suspect noise in the harness. i re-wired the tps. easy, fast and it fixed my problem.

 

[ndurbin]

theres no button there. i even took a small screwdriver and tried pushing on it. theres is nothing there that pushes in. just a small rough spot oppisite of the bulge.



shendren, i've read alil bit about your fix for rewiring the TPS and well keep it in mind.

 

[Joe G.]

There certainly is a button there. I've pushed it in many times. The whole flat side is a button. It's pretty stiff. Which is another reason that I use a C-clamp to press it. The transmission in your '94 is a 47RH like in my '95. The 47RE used in later trucks has a different setup there. When you are standing by your truck fender looking at it, the pointed end of the cable housing is to the left. Then there is the metal bracket holding the black cube just to the right of that. Most of the cube is to the right of the bracket. The bulge that houses the button spring should be toward the engine from you and angled down. The flat side toward you is the button.

 

[ndurbin]

Then calling it a "button" is a bit confusing to someone that hasn't done it before if it's not actually a "button".



I'll look at it again in the morning.

 

[Joe G.]

That's what the service manual calls it. It took me quite a little while to figure it out because the service manual just says to press the button with no description or illustration of it at all. If you press and hold it the nose of the cable housing can be moved in or out. The small rough spot was probably caused by a c-clamp or a pair of pliers.

 

[shendren]

i say bill's capacitors didn't work, but bill was a huge help while i diagosed the problem... . he is very knowledgable with these transmissions and the electrical side of things...

 

[ndurbin]

I checked the kick down cable again found the flat side that pushes in and it needs a bit of adjustment and I took the TPS off and cleaned the crap out of it. Thats as far as I got before my fingers turned into ice. Went and test drove it after that I didn't get the TPS quite right so it needs to be adjusted. I'll do that tomorrow along with the kick down cable at work in the shop.



Shendren: who is Bill?

 

[shendren]

bill kondolay. diesel transmission technology (DTT)... .



http://www.dieseltrans.com/



give him a call. he is very helpful.

 

[SBozeman]

Check the voltage again. Was the 4. 43 volts at idle or wide open throttle. I think you were headed in the right direction before. The manual incates that the voltage should be 1. 0 +/- . 2 at idle and 2. 2 to 2. 9 higher than idle at wide open throttle. Assuming its the same as a 98.

 

[shendren]

that's the signal voltage. from the orange to ground. the power should be 5v. (that's from the violet to ground).

 

[ndurbin]

SBozeman, I got the 4. 43 with the key on and the harness disconnected from the TPS. I got these directions from a link in a post to the dodgeram.org website.



The wiring colors threw me at first cause they didn't match the directions.

 

[shendren]

ndurbin,



that 4. 43v should have been closer to 5. v.



you need to tap 1 pigtail onto the signal wire and hook a dvm to it and take it for a drive with the dvm in the cab with you. it takes 2 minutes.



btw, what are the colors on your tps?



they should be:

ground - black with a dark blue stripe

power - violet with a white stripe

signal - orange with dark blue stripe.



i think that's what fritz's site has... ... .



http://www.dodgeram.org/tech/transmission/automatic/TPS_adjust.htm

 

[shendren]

you should probably tap the signal wire on the passenger side. close to the pcm to see what kind of signal the pcm is getting. i would bet it is flucuating quite a bit.



when you tap it, go ahead and tap the 5v power there as well.



i ended up tapping the signal and ground at the tps and at the pcm.

 

[shendren]

that last sentence should have read:



i ended up tapping the signal and power at the tps and at the pcm.