Engine/Transmission (1994 - 1998) Auto Transmission shifting problems

[Mauseth]

I have a 97 automatic, 4 wheel drive. When the transmission gets close to lock up, it will shift up, then back down and then stays in the lower gear until high rpms, then will finally shift out again. Is this the throttle position sensor? It seems like it is only under a light throttle that this happens. If it is the sensor, is it a bolt on part that can be done easily by myself, or do I need professional help?

 

[Smokin Ram]

tps

the tps , throttle position sensor sounds like the culprit. its a bolt on part on the front of your pump, its a small plastic box that bolts onto the throttle linkage at the front left of the pump. It can be calibrated, if you are in adverse weather ie cold, rain etc. . take it off or warm it up to dry it out, i have a 94 and it keeps doing funny things , i live in Canada and the tps will get moisture in it from freezing and thawing. You can get a new one but there not cheap. hope this helps

 

[WBusa]

I've just recently had a lot of experience with this, and recommend that you inspect what I have come to think of as 'The Axis of Evil': the throttle linkage, the throttle position sensor (TPS), and the throttle valve cable (AKA 'kickdown' cable). These are simple adjustments and you can do them, but you have to pay attention to getting all three right... when you mess with one, you always need to check the other two.



First, check your ATF level and condition. If good, go on to check your adjustments:



First check your throttle linkage: distance from the center of the ball on the throttle lever to the rear face of the cable mounting bracket should be 126. 5 mm (5"), as precisely as you can get it, when the lever is at low idle position. If not, clamp a small vicegrip on the flat of the throttle linkage and hold it from rotating while you loosen the locknuts at either end (one is right-handed, other is left-handed, both are 10mm), then turn the linkage one way or the other until the throttle lever ball to rear face of cable mounting bracket is 126. 5 mm. Then tighten the locknuts back up. This whole process is easier if you first pull off the intake manifold in order to get the big intake air pipe out of your way.



Next, check the voltage being output from your throttle position sensor. It should be 1. 0 +/- 0. 2 at low idle position, and two-point-something volts higher at WOT. It is not officially adjustable, but can easily be adjusted (thank goodness -- its a $200 part!). See: http://www.dodgeram.org/tech/transmission/automatic/TPS_adjust.htm. Oh, and here's a tip that might prove helpful: the instructions talk about shoving your voltmeter probes in the back of the connector in order to take the reading, or else shoving paper clips in there. If your connector, like mine, is sealed closed, just do this: steal from your wife or significant other the sharpest, thinnest sewing needle you can find. Stick it right into the wire you're trying to get a reading from, then touch the needle with your test probe. Voila. If the needle is thin and sharp, the hole you make in the insulation will seal itself back up once you remove the needle 'good enough for government work'. I use this trick all the time to get readings off of stranded wires that aren't showing any copper. Works like a champ.



Finally, adjust your throttle valve cable (kickdown cable). See: http://www.dodgeram.org/tech/transmission/automatic/throttle_lever_adj.htm



Voice of experience: doing just one of these without doing the other two is like trying to level a table by shortening one leg (i. e. , not bloody likely to yield a satisfying result). This is, however, real simple stuff. Have fun!

 

[bmoeller]

Welcome to the TDR!



The TPS can be cleaned. I need to do mine again. It started acting up again today.



Get some Electronic spray cleaner. With the little tube on the ned of the can, spray it down the shaft into the TPS. Work the linkage back and forth to work it in there. Do this several times. May enough to solve the problem. Worked for me before.

 

[Dfuruness]

Welcome to the TDR. Yep I think it is the TPS. I sprayed mine with electrical contact cleaner and I have had no problems since



Don

 

[Mauseth]

It's been a long time since I have had the opportunity to be able to log into the TDR website. I have been a faithful member of TDR for many years though. I want to thank all of you who answered my question and helped solve my problem. I cleaned up the linkage and that seemed to take care of it. I really appreciate your help!!!